521856436143426 has 64 divisors (see below), whose sum is σ = 1086240835468800. Its totient is φ = 167003268638976.

The previous prime is 521856436143389. The next prime is 521856436143473. The reversal of 521856436143426 is 624341634658125.

It is a self number, because there is not a number n which added to its sum of digits gives 521856436143426.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 104992645 + ... + 109850663.

It is an arithmetic number, because the mean of its divisors is an integer number (16972513054200).

Almost surely, 2^{521856436143426} is an apocalyptic number.

521856436143426 is an abundant number, since it is smaller than the sum of its proper divisors (564384399325374).

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

521856436143426 is a wasteful number, since it uses less digits than its factorization.

521856436143426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4865183.

The product of its digits is 99532800, while the sum is 60.

The spelling of 521856436143426 in words is "five hundred twenty-one trillion, eight hundred fifty-six billion, four hundred thirty-six million, one hundred forty-three thousand, four hundred twenty-six".