521436864 has 224 divisors, whose sum is σ = 1605832704. Its totient is φ = 148008960.

The previous prime is 521436859. The next prime is 521436889. The reversal of 521436864 is 468634125.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1779502 + ... + 1779794.

It is an arithmetic number, because the mean of its divisors is an integer number (7168896).

Almost surely, 2^521436864 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 521436864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (802916352).

521436864 is an abundant number, since it is smaller than the sum of its proper divisors (1084395840).

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

521436864 is a wasteful number, since it uses less digits than its factorization.

521436864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 375 (or 365 counting only the distinct ones).

The product of its digits is 138240, while the sum is 39.

The square root of 521436864 is about 22834.9920954661. The cubic root of 521436864 is about 804.8851418499.

The spelling of 521436864 in words is "five hundred twenty-one million, four hundred thirty-six thousand, eight hundred sixty-four".