661607520 has 96 divisors (see below), whose sum is σ = 2381799168. Its totient is φ = 151223808.

The previous prime is 661607501. The next prime is 661607587. The reversal of 661607520 is 25706166.

661607520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 95094 + ... + 101813.

It is an arithmetic number, because the mean of its divisors is an integer number (24810408).

Almost surely, 2^661607520 is an apocalyptic number.

661607520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

661607520 is an abundant number, since it is smaller than the sum of its proper divisors (1720191648).

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

661607520 is a wasteful number, since it uses less digits than its factorization.

661607520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196932 (or 196924 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 33.

The square root of 661607520 is about 25721.7324455411. The cubic root of 661607520 is about 871.3650653865.

The spelling of 661607520 in words is "six hundred sixty-one million, six hundred seven thousand, five hundred twenty".