18972171634 has 16 divisors (see below), whose sum is σ = 30662739072. Its totient is φ = 8751991248.

The previous prime is 18972171601. The next prime is 18972171661. The reversal of 18972171634 is 43617127981.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 130074 + ... + 234229.

It is an arithmetic number, because the mean of its divisors is an integer number (1916421192).

Almost surely, 2^18972171634 is an apocalyptic number.

18972171634 is a deficient number, since it is larger than the sum of its proper divisors (11690567438).

18972171634 is a wasteful number, since it uses less digits than its factorization.

18972171634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366321.

The product of its digits is 508032, while the sum is 49.

The spelling of 18972171634 in words is "eighteen billion, nine hundred seventy-two million, one hundred seventy-one thousand, six hundred thirty-four".