640057760 has 24 divisors (see below), whose sum is σ = 1512136836. Its totient is φ = 256023040.

The previous prime is 640057751. The next prime is 640057787. The reversal of 640057760 is 67750046.

It can be written as a sum of positive squares in 2 ways, for example, as 579653776 + 60403984 = 24076^2 + 7772^2 .

It is a super-2 number, since 2×640057760² = 819347872272435200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 640057760.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2000021 + ... + 2000340.

Almost surely, 2^640057760 is an apocalyptic number.

It is an amenable number.

640057760 is an abundant number, since it is smaller than the sum of its proper divisors (872079076).

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

640057760 is a wasteful number, since it uses less digits than its factorization.

640057760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4000376 (or 4000368 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 35.

The square root of 640057760 is about 25299.3628378266. The cubic root of 640057760 is about 861.7998002637.

The spelling of 640057760 in words is "six hundred forty million, fifty-seven thousand, seven hundred sixty".