640086025 has 12 divisors (see below), whose sum is σ = 801892252. Its totient is φ = 506787840.

The previous prime is 640086001. The next prime is 640086049. The reversal of 640086025 is 520680046.

It is an interprime number because it is at equal distance from previous prime (640086001) and next prime (640086049).

It can be written as a sum of positive squares in 6 ways, for example, as 18481401 + 621604624 = 4299^2 + 24932^2 .

It is not a de Polignac number, because 640086025 - 2¹⁵ = 640053257 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 129552 + ... + 134401.

Almost surely, 2^640086025 is an apocalyptic number.

It is an amenable number.

640086025 is a deficient number, since it is larger than the sum of its proper divisors (161806227).

640086025 is a wasteful number, since it uses less digits than its factorization.

640086025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264060 (or 264055 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 640086025 is about 25299.9214425658. The cubic root of 640086025 is about 861.8124857921.

The spelling of 640086025 in words is "six hundred forty million, eighty-six thousand, twenty-five".