656605457 has 4 divisors (see below), whose sum is σ = 656747520. Its totient is φ = 656463396.

The previous prime is 656605429. The next prime is 656605511. The reversal of 656605457 is 754506656.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 656605457 - 2¹⁸ = 656343313 is a prime.

It is a super-2 number, since 2×656605457² = 862261452324357698, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (656601457) 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, 63857 + ... + 73422.

It is an arithmetic number, because the mean of its divisors is an integer number (164186880).

Almost surely, 2^656605457 is an apocalyptic number.

It is an amenable number.

656605457 is a deficient number, since it is larger than the sum of its proper divisors (142063).

656605457 is a wasteful number, since it uses less digits than its factorization.

656605457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142062.

The product of its (nonzero) digits is 756000, while the sum is 44.

The square root of 656605457 is about 25624.3137859339. The cubic root of 656605457 is about 869.1635316962.

It can be divided in two parts, 65660 and 5457, that added together give a palindrome (71117).

The spelling of 656605457 in words is "six hundred fifty-six million, six hundred five thousand, four hundred fifty-seven".