18640925644 has 24 divisors (see below), whose sum is σ = 37134494208. Its totient is φ = 8104749840.

The previous prime is 18640925623. The next prime is 18640925717. The reversal of 18640925644 is 44652904681.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9208932 + ... + 9210955.

It is an arithmetic number, because the mean of its divisors is an integer number (1547270592).

Almost surely, 2^18640925644 is an apocalyptic number.

It is an amenable number.

18640925644 is a deficient number, since it is larger than the sum of its proper divisors (18493568564).

18640925644 is a wasteful number, since it uses less digits than its factorization.

18640925644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18419925 (or 18419923 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 49.

The spelling of 18640925644 in words is "eighteen billion, six hundred forty million, nine hundred twenty-five thousand, six hundred forty-four".