644514625 has 32 divisors (see below), whose sum is σ = 888765696. Its totient is φ = 464147200.

The previous prime is 644514613. The next prime is 644514631. The reversal of 644514625 is 526415446.

It is not a de Polignac number, because 644514625 - 2⁹ = 644514113 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 42282 + ... + 55468.

It is an arithmetic number, because the mean of its divisors is an integer number (27773928).

Almost surely, 2^644514625 is an apocalyptic number.

It is an amenable number.

644514625 is a deficient number, since it is larger than the sum of its proper divisors (244251071).

644514625 is a wasteful number, since it uses less digits than its factorization.

644514625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13242 (or 13232 counting only the distinct ones).

The product of its digits is 115200, while the sum is 37.

The square root of 644514625 is about 25387.2925890100. The cubic root of 644514625 is about 863.7954767276.

The spelling of 644514625 in words is "six hundred forty-four million, five hundred fourteen thousand, six hundred twenty-five".