21113479744 has 112 divisors (see below), whose sum is σ = 50801950720. Its totient is φ = 8504455680.

The previous prime is 21113479727. The next prime is 21113479781. The reversal of 21113479744 is 44797431112.

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 21113479744.

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, 1071259 + ... + 1090789.

Almost surely, 2^21113479744 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21113479744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25400975360).

21113479744 is an abundant number, since it is smaller than the sum of its proper divisors (29688470976).

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

21113479744 is a wasteful number, since it uses less digits than its factorization.

21113479744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19696 (or 19686 counting only the distinct ones).

The product of its digits is 169344, while the sum is 43.

The spelling of 21113479744 in words is "twenty-one billion, one hundred thirteen million, four hundred seventy-nine thousand, seven hundred forty-four".