521423631216 has 120 divisors (see below), whose sum is σ = 1508044621824. Its totient is φ = 168010266240.

The previous prime is 521423631193. The next prime is 521423631221. The reversal of 521423631216 is 612136324125.

521423631216 is a `hidden beast` number, since 5 + 2 + 1 + 4 + 2 + 3 + 631 + 2 + 16 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3893725 + ... + 4025411.

Almost surely, 2^521423631216 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 521423631216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (754022310912).

521423631216 is an abundant number, since it is smaller than the sum of its proper divisors (986620990608).

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

521423631216 is a wasteful number, since it uses less digits than its factorization.

521423631216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132619 (or 132610 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The spelling of 521423631216 in words is "five hundred twenty-one billion, four hundred twenty-three million, six hundred thirty-one thousand, two hundred sixteen".