640834696 has 32 divisors (see below), whose sum is σ = 1216215000. Its totient is φ = 316535296.

The previous prime is 640834693. The next prime is 640834723. The reversal of 640834696 is 696438046.

It can be written as a sum of positive squares in 4 ways, for example, as 640798596 + 36100 = 25314^2 + 190^2 .

It is not an unprimeable number, because it can be changed into a prime (640834693) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 233460 + ... + 236188.

Almost surely, 2^640834696 is an apocalyptic number.

It is an amenable number.

640834696 is a deficient number, since it is larger than the sum of its proper divisors (575380304).

640834696 is a wasteful number, since it uses less digits than its factorization.

640834696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3081 (or 3077 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 46.

The square root of 640834696 is about 25314.7130341231. The cubic root of 640834696 is about 862.1483586787.

The spelling of 640834696 in words is "six hundred forty million, eight hundred thirty-four thousand, six hundred ninety-six".