640773032 has 8 divisors (see below), whose sum is σ = 1201449450. Its totient is φ = 320386512.

The previous prime is 640773019. The next prime is 640773041. The reversal of 640773032 is 230377046.

It can be written as a sum of positive squares in only one way, i.e., 531486916 + 109286116 = 23054^2 + 10454^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 640773032.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40048307 + ... + 40048322.

Almost surely, 2^640773032 is an apocalyptic number.

It is an amenable number.

640773032 is a deficient number, since it is larger than the sum of its proper divisors (560676418).

640773032 is a wasteful number, since it uses less digits than its factorization.

640773032 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80096635 (or 80096631 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 32.

The square root of 640773032 is about 25313.4950569849. The cubic root of 640773032 is about 862.1207045259.

The spelling of 640773032 in words is "six hundred forty million, seven hundred seventy-three thousand, thirty-two".