521373136 has 80 divisors (see below), whose sum is σ = 1116156240. Its totient is φ = 234823680.

The previous prime is 521373109. The next prime is 521373169. The reversal of 521373136 is 631373125.

It can be written as a sum of positive squares in 8 ways, for example, as 47004736 + 474368400 = 6856^2 + 21780^2 .

It is a junction number, because it is equal to n+sod(n) for n = 521373098 and 521373107.

It is a congruent number.

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, 1238206 + ... + 1238626.

It is an arithmetic number, because the mean of its divisors is an integer number (13951953).

Almost surely, 2^521373136 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 521373136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (558078120).

521373136 is an abundant number, since it is smaller than the sum of its proper divisors (594783104).

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

521373136 is a wasteful number, since it uses less digits than its factorization.

521373136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 632 (or 626 counting only the distinct ones).

The product of its digits is 11340, while the sum is 31.

The square root of 521373136 is about 22833.5966505498. The cubic root of 521373136 is about 804.8523505293.

The spelling of 521373136 in words is "five hundred twenty-one million, three hundred seventy-three thousand, one hundred thirty-six".