657653661 has 40 divisors (see below), whose sum is σ = 1133768064. Its totient is φ = 372120480.

The previous prime is 657653641. The next prime is 657653681. The reversal of 657653661 is 166356756.

657653661 is a `hidden beast` number, since 6 + 57 + 6 + 536 + 61 = 666.

It is an interprime number because it is at equal distance from previous prime (657653641) and next prime (657653681).

It is not a de Polignac number, because 657653661 - 2⁷ = 657653533 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (657653641) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 52771 + ... + 64031.

Almost surely, 2^657653661 is an apocalyptic number.

It is an amenable number.

657653661 is a deficient number, since it is larger than the sum of its proper divisors (476114403).

657653661 is a wasteful number, since it uses less digits than its factorization.

657653661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11383 (or 11374 counting only the distinct ones).

The product of its digits is 680400, while the sum is 45.

The square root of 657653661 is about 25644.7589382314. The cubic root of 657653661 is about 869.6257962647.

The spelling of 657653661 in words is "six hundred fifty-seven million, six hundred fifty-three thousand, six hundred sixty-one".