521623680 has 128 divisors (see below), whose sum is σ = 1670613120. Its totient is φ = 138436608.

The previous prime is 521623657. The next prime is 521623681. The reversal of 521623680 is 86326125.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (521623681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 504444 + ... + 505476.

It is an arithmetic number, because the mean of its divisors is an integer number (13051665).

Almost surely, 2^521623680 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 521623680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (835306560).

521623680 is an abundant number, since it is smaller than the sum of its proper divisors (1148989440).

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

521623680 is a wasteful number, since it uses less digits than its factorization.

521623680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1318 (or 1306 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 521623680 is about 22839.0822932972. The cubic root of 521623680 is about 804.9812528587.

The spelling of 521623680 in words is "five hundred twenty-one million, six hundred twenty-three thousand, six hundred eighty".