521400113455220 has 24 divisors (see below), whose sum is σ = 1097336168774664. Its totient is φ = 208103677664256.

The previous prime is 521400113455201. The next prime is 521400113455271. The reversal of 521400113455220 is 22554311004125.

It can be written as a sum of positive squares in 4 ways, for example, as 280471789333264 + 240928324121956 = 16747292^2 + 15521866^2 .

It is a super-2 number, since 2×521400113455220² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

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, 28522972997 + ... + 28522991276.

It is an arithmetic number, because the mean of its divisors is an integer number (45722340365611).

Almost surely, 2^{521400113455220} is an apocalyptic number.

It is an amenable number.

521400113455220 is an abundant number, since it is smaller than the sum of its proper divisors (575936055319444).

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

521400113455220 is a wasteful number, since it uses less digits than its factorization.

521400113455220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57045964739 (or 57045964737 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 35.

Adding to 521400113455220 its reverse (22554311004125), we get a palindrome (543954424459345).

The spelling of 521400113455220 in words is "five hundred twenty-one trillion, four hundred billion, one hundred thirteen million, four hundred fifty-five thousand, two hundred twenty".