644325045 has 128 divisors (see below), whose sum is σ = 1347978240. Its totient is φ = 255467520.

The previous prime is 644325001. The next prime is 644325107. The reversal of 644325045 is 540523446.

It is not a de Polignac number, because 644325045 - 2⁷ = 644324917 is a prime.

It is a super-2 number, since 2×644325045² = 830309527228504050, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 644324997 and 644325015.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1622787 + ... + 1623183.

It is an arithmetic number, because the mean of its divisors is an integer number (10531080).

Almost surely, 2^644325045 is an apocalyptic number.

644325045 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

644325045 is an abundant number, since it is smaller than the sum of its proper divisors (703653195).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644325045 is a wasteful number, since it uses less digits than its factorization.

644325045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495.

The product of its (nonzero) digits is 57600, while the sum is 33.

The square root of 644325045 is about 25383.5585566721. The cubic root of 644325045 is about 863.7107750524.

The spelling of 644325045 in words is "six hundred forty-four million, three hundred twenty-five thousand, forty-five".