640337692 has 12 divisors (see below), whose sum is σ = 1123146640. Its totient is φ = 319438656.

The previous prime is 640337681. The next prime is 640337699. The reversal of 640337692 is 296733046.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640337699) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 180573 + ... + 184084.

Almost surely, 2^640337692 is an apocalyptic number.

It is an amenable number.

640337692 is a deficient number, since it is larger than the sum of its proper divisors (482808948).

640337692 is a wasteful number, since it uses less digits than its factorization.

640337692 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365100 (or 365098 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 40.

The square root of 640337692 is about 25304.8946253487. The cubic root of 640337692 is about 861.9254192288.

The spelling of 640337692 in words is "six hundred forty million, three hundred thirty-seven thousand, six hundred ninety-two".