640275625 has 20 divisors (see below), whose sum is σ = 872833104. Its totient is φ = 465650000.

The previous prime is 640275619. The next prime is 640275631. The reversal of 640275625 is 526572046.

It is an interprime number because it is at equal distance from previous prime (640275619) and next prime (640275631).

It is not a de Polignac number, because 640275625 - 2⁹ = 640275113 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 39691 + ... + 53440.

Almost surely, 2^640275625 is an apocalyptic number.

It is an amenable number.

640275625 is a deficient number, since it is larger than the sum of its proper divisors (232557479).

640275625 is an equidigital number, since it uses as much as digits as its factorization.

640275625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93162 (or 93147 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 37.

The square root of 640275625 is about 25303.6682123363. The cubic root of 640275625 is about 861.8975699371.

The spelling of 640275625 in words is "six hundred forty million, two hundred seventy-five thousand, six hundred twenty-five".