661136275 has 12 divisors (see below), whose sum is σ = 839805624. Its totient is φ = 516008000.

The previous prime is 661136269. The next prime is 661136291. The reversal of 661136275 is 572631166.

It is not a de Polignac number, because 661136275 - 2⁵ = 661136243 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 321481 + ... + 323530.

It is an arithmetic number, because the mean of its divisors is an integer number (69983802).

Almost surely, 2^661136275 is an apocalyptic number.

661136275 is a deficient number, since it is larger than the sum of its proper divisors (178669349).

661136275 is a wasteful number, since it uses less digits than its factorization.

661136275 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 645062 (or 645057 counting only the distinct ones).

The product of its digits is 45360, while the sum is 37.

The square root of 661136275 is about 25712.5703693738. The cubic root of 661136275 is about 871.1581330542.

The spelling of 661136275 in words is "six hundred sixty-one million, one hundred thirty-six thousand, two hundred seventy-five".