18915279936 has 112 divisors (see below), whose sum is σ = 57322151040. Its totient is φ = 5392465920.

The previous prime is 18915279923. The next prime is 18915279941. The reversal of 18915279936 is 63997251981.

It is a tau number, because it is divible by the number of its divisors (112).

It is a self number, because there is not a number n which added to its sum of digits gives 18915279936.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 604320 + ... + 634848.

It is an arithmetic number, because the mean of its divisors is an integer number (511804920).

Almost surely, 2^18915279936 is an apocalyptic number.

18915279936 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18915279936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28661075520).

18915279936 is an abundant number, since it is smaller than the sum of its proper divisors (38406871104).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18915279936 is a wasteful number, since it uses less digits than its factorization.

18915279936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31012 (or 31002 counting only the distinct ones).

The product of its digits is 7348320, while the sum is 60.

The spelling of 18915279936 in words is "eighteen billion, nine hundred fifteen million, two hundred seventy-nine thousand, nine hundred thirty-six".