661436960 has 48 divisors (see below), whose sum is σ = 1581503616. Its totient is φ = 261381888.

The previous prime is 661436929. The next prime is 661436983. The reversal of 661436960 is 69634166.

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, 11624 + ... + 38183.

It is an arithmetic number, because the mean of its divisors is an integer number (32947992).

Almost surely, 2^661436960 is an apocalyptic number.

It is an amenable number.

661436960 is an abundant number, since it is smaller than the sum of its proper divisors (920066656).

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

661436960 is a wasteful number, since it uses less digits than its factorization.

661436960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49905 (or 49897 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 41.

The square root of 661436960 is about 25718.4167475372. The cubic root of 661436960 is about 871.2901807084.

The spelling of 661436960 in words is "six hundred sixty-one million, four hundred thirty-six thousand, nine hundred sixty".