640607976 has 48 divisors (see below), whose sum is σ = 1738865700. Its totient is φ = 213057792.

The previous prime is 640607959. The next prime is 640607977. The reversal of 640607976 is 679706046.

It can be written as a sum of positive squares in 2 ways, for example, as 628705476 + 11902500 = 25074^2 + 3450^2 .

It is not an unprimeable number, because it can be changed into a prime (640607977) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23170 + ... + 42638.

Almost surely, 2^640607976 is an apocalyptic number.

It is an amenable number.

640607976 is an abundant number, since it is smaller than the sum of its proper divisors (1098257724).

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

640607976 is a wasteful number, since it uses less digits than its factorization.

640607976 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19938 (or 19931 counting only the distinct ones).

The product of its (nonzero) digits is 381024, while the sum is 45.

The square root of 640607976 is about 25310.2346097384. The cubic root of 640607976 is about 862.0466739369.

The spelling of 640607976 in words is "six hundred forty million, six hundred seven thousand, nine hundred seventy-six".