The Number
645
Six Hundred and Forty-Five
Nearby Numbers
Positive, nonzero integers within three units
Scientific Notation
Scientific notation expresses a quantity as the product of its significand with 10 raised to an integer exponent.
6.45e2
Reciprocal
A number multiplied with its reciprocal is one.
0.0015503875968992248
The reciprocal of 645.
Palindrome?
A numerical palindrome has the same value when all of its digits are reversed.
The number 645 is not a palindrome.
Not A Prime Number
A prime number is a positive integer that is divisible only by itself and one.
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.
Six hundred and forty-five is a composite number with 8 total factors (including 1 and itself).
Prime Factors
The number six hundred and forty-five has the following 3 prime factors:
Prime Factorization
The prime factorization of a positive integer is the unique list of prime factors together with their multiplicities
31
·
51
·
431
= 645
Base Conversions
The number six hundred and forty-five in 35 different bases