521680000 has 80 divisors (see below), whose sum is σ = 1298888910. Its totient is φ = 208640000.

The previous prime is 521679989. The next prime is 521680001. The reversal of 521680000 is 86125.

It is a happy number.

It can be written as a sum of positive squares in 5 ways, for example, as 66455104 + 455224896 = 8152^2 + 21336^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (521680001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 76740 + ... + 83260.

Almost surely, 2^521680000 is an apocalyptic number.

521680000 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 521680000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (649444455).

521680000 is an abundant number, since it is smaller than the sum of its proper divisors (777208910).

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

521680000 is an frugal number, since it uses more digits than its factorization.

521680000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6555 (or 6528 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 521680000 is about 22840.3152342519. The cubic root of 521680000 is about 805.0102232412.

The spelling of 521680000 in words is "five hundred twenty-one million, six hundred eighty thousand".