521662680 has 768 divisors, whose sum is σ = 2377589760. Its totient is φ = 99532800.

The previous prime is 521662679. The next prime is 521662703. The reversal of 521662680 is 86266125.

521662680 is a `hidden beast` number, since 5 + 21 + 6 + 626 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

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 191 ways as a sum of consecutive naturals, for example, 12723460 + ... + 12723500.

It is an arithmetic number, because the mean of its divisors is an integer number (3095820).

Almost surely, 2^521662680 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 521662680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1188794880).

521662680 is an abundant number, since it is smaller than the sum of its proper divisors (1855927080).

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

521662680 is a wasteful number, since it uses less digits than its factorization.

521662680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102 (or 86 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 521662680 is about 22839.9360769683. The cubic root of 521662680 is about 805.0013142476.

It can be divided in two parts, 5216 and 62680, that added together give a triangular number (67896 = T₃₆₈).

The spelling of 521662680 in words is "five hundred twenty-one million, six hundred sixty-two thousand, six hundred eighty".