521856420114018 has 128 divisors (see below), whose sum is σ = 1203013416084480. Its totient is φ = 149254280536320.

The previous prime is 521856420113971. The next prime is 521856420114061. The reversal of 521856420114018 is 810411024658125.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 790029696 + ... + 790689972.

It is an arithmetic number, because the mean of its divisors is an integer number (9398542313160).

Almost surely, 2^{521856420114018} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 521856420114018, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (601506708042240).

521856420114018 is an abundant number, since it is smaller than the sum of its proper divisors (681156995970462).

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

521856420114018 is a wasteful number, since it uses less digits than its factorization.

521856420114018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 662672.

The product of its (nonzero) digits is 614400, while the sum is 48.

The spelling of 521856420114018 in words is "five hundred twenty-one trillion, eight hundred fifty-six billion, four hundred twenty million, one hundred fourteen thousand, eighteen".