The Number

1645

One Thousand Six Hundred and Forty-Five

Nearby Numbers

Positive, nonzero integers within three units

1642
One Thousand Six Hundred and Forty-Two
1643
One Thousand Six Hundred and Forty-Three
1644
One Thousand Six Hundred and Forty-Four
1646
One Thousand Six Hundred and Forty-Six
1647
One Thousand Six Hundred and Forty-Seven
1648
One Thousand Six Hundred and Forty-Eight

Scientific Notation

Scientific notation expresses a quantity as the product of its significand with 10 raised to an integer exponent.

1.645e3

Reciprocal

A number multiplied with its reciprocal is one.

0.0006079027355623101

The reciprocal of 1645.

Palindrome?

A numerical palindrome has the same value when all of its digits are reversed.

The number 1645 is not a palindrome.

Not A Prime Number

A prime number is a positive integer that is divisible only by itself and one.

One thousand six hundred and forty-five is a composite number with 8 total factors (including 1 and itself).   See primes in Base 10 Decimal

A Composite

Composites have more than just these two factors.

One thousand six hundred and forty-five is a composite number with 8 total factors (including 1 and itself).

Prime Factors

The prime factors of a positive integer are the integers that divide it exactly and are also prime.

The number one thousand six hundred and forty-five has the following 3 prime factors:

5
Five
7
Seven
47
Forty-Seven

Prime Factorization

The prime factorization of a positive integer is the unique list of prime factors together with their multiplicities

51 · 71 · 471 = 1645

Base Conversions

The number one thousand six hundred and forty-five in 35 different bases