680637520 has 40 divisors (see below), whose sum is σ = 1586030184. Its totient is φ = 271644672.

The previous prime is 680637487. The next prime is 680637527. The reversal of 680637520 is 25736086.

It can be written as a sum of positive squares in 4 ways, for example, as 376204816 + 304432704 = 19396^2 + 17448^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 680637520.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (680637527) 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 7 ways as a sum of consecutive naturals, for example, 27252 + ... + 45868.

Almost surely, 2^680637520 is an apocalyptic number.

It is an amenable number.

680637520 is an abundant number, since it is smaller than the sum of its proper divisors (905392664).

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

680637520 is a wasteful number, since it uses less digits than its factorization.

680637520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19087 (or 19081 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 37.

The square root of 680637520 is about 26089.0306450815. The cubic root of 680637520 is about 879.6406590711.

The spelling of 680637520 in words is "six hundred eighty million, six hundred thirty-seven thousand, five hundred twenty".