640772996 has 24 divisors (see below), whose sum is σ = 1149528576. Its totient is φ = 312387840.

The previous prime is 640772933. The next prime is 640773019. The reversal of 640772996 is 699277046.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44660 + ... + 57236.

It is an arithmetic number, because the mean of its divisors is an integer number (47897024).

Almost surely, 2^640772996 is an apocalyptic number.

It is an amenable number.

640772996 is a deficient number, since it is larger than the sum of its proper divisors (508755580).

640772996 is a wasteful number, since it uses less digits than its factorization.

640772996 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12899 (or 12897 counting only the distinct ones).

The product of its (nonzero) digits is 1143072, while the sum is 50.

The square root of 640772996 is about 25313.4943459018. The cubic root of 640772996 is about 862.1206883807.

The spelling of 640772996 in words is "six hundred forty million, seven hundred seventy-two thousand, nine hundred ninety-six".