521248256640 has 768 divisors, whose sum is σ = 1974613006080. Its totient is φ = 126303141888.

The previous prime is 521248256629. The next prime is 521248256699. The reversal of 521248256640 is 46652842125.

521248256640 is a `hidden beast` number, since 5 + 2 + 1 + 2 + 4 + 82 + 566 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

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 95 ways as a sum of consecutive naturals, for example, 210774444 + ... + 210776916.

It is an arithmetic number, because the mean of its divisors is an integer number (2571110685).

Almost surely, 2^521248256640 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 521248256640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (987306503040).

521248256640 is an abundant number, since it is smaller than the sum of its proper divisors (1453364749440).

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

521248256640 is a wasteful number, since it uses less digits than its factorization.

521248256640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2601 (or 2586 counting only the distinct ones).

The product of its (nonzero) digits is 921600, while the sum is 45.

The spelling of 521248256640 in words is "five hundred twenty-one billion, two hundred forty-eight million, two hundred fifty-six thousand, six hundred forty".