1639640936 has 16 divisors (see below), whose sum is σ = 3077015040. Its totient is φ = 819103600.

The previous prime is 1639640921. The next prime is 1639640941. The reversal of 1639640936 is 6390469361.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 79826 + ... + 98241.

It is an arithmetic number, because the mean of its divisors is an integer number (192313440).

Almost surely, 2^1639640936 is an apocalyptic number.

It is an amenable number.

1639640936 is a deficient number, since it is larger than the sum of its proper divisors (1437374104).

1639640936 is a wasteful number, since it uses less digits than its factorization.

1639640936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179224 (or 179220 counting only the distinct ones).

The product of its (nonzero) digits is 629856, while the sum is 47.

The square root of 1639640936 is about 40492.4799932037. The cubic root of 1639640936 is about 1179.1876377419.

The spelling of 1639640936 in words is "one billion, six hundred thirty-nine million, six hundred forty thousand, nine hundred thirty-six".