668732520 has 32 divisors (see below), whose sum is σ = 2006197920. Its totient is φ = 178328640.

The previous prime is 668732513. The next prime is 668732539. The reversal of 668732520 is 25237866.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2786266 + ... + 2786505.

It is an arithmetic number, because the mean of its divisors is an integer number (62693685).

Almost surely, 2^668732520 is an apocalyptic number.

668732520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

668732520 is an abundant number, since it is smaller than the sum of its proper divisors (1337465400).

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

668732520 is a wasteful number, since it uses less digits than its factorization.

668732520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5572785 (or 5572781 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 39.

The square root of 668732520 is about 25859.8631086864. The cubic root of 668732520 is about 874.4818788393.

The spelling of 668732520 in words is "six hundred sixty-eight million, seven hundred thirty-two thousand, five hundred twenty".