661565132 has 12 divisors (see below), whose sum is σ = 1225841400. Its totient is φ = 311324736.

The previous prime is 661565119. The next prime is 661565137. The reversal of 661565132 is 231565166.

It is a junction number, because it is equal to n+sod(n) for n = 661565092 and 661565101.

It is not an unprimeable number, because it can be changed into a prime (661565137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4864382 + ... + 4864517.

It is an arithmetic number, because the mean of its divisors is an integer number (102153450).

Almost surely, 2^661565132 is an apocalyptic number.

It is an amenable number.

661565132 is a deficient number, since it is larger than the sum of its proper divisors (564276268).

661565132 is a wasteful number, since it uses less digits than its factorization.

661565132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9728920 (or 9728918 counting only the distinct ones).

The product of its digits is 32400, while the sum is 35.

The square root of 661565132 is about 25720.9084598503. The cubic root of 661565132 is about 871.3464560599.

The spelling of 661565132 in words is "six hundred sixty-one million, five hundred sixty-five thousand, one hundred thirty-two".