656543231 has 4 divisors (see below), whose sum is σ = 656748312. Its totient is φ = 656338152.

The previous prime is 656543219. The next prime is 656543249. The reversal of 656543231 is 132345656.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-656543231 is a prime.

It is a super-2 number, since 2×656543231² = 862098028343838722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 656543191 and 656543200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656143231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97661 + ... + 104166.

It is an arithmetic number, because the mean of its divisors is an integer number (164187078).

Almost surely, 2^656543231 is an apocalyptic number.

656543231 is a deficient number, since it is larger than the sum of its proper divisors (205081).

656543231 is a wasteful number, since it uses less digits than its factorization.

656543231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205080.

The product of its digits is 64800, while the sum is 35.

The square root of 656543231 is about 25623.0995587966. The cubic root of 656543231 is about 869.1360741731.

Adding to 656543231 its reverse (132345656), we get a palindrome (788888887).

The spelling of 656543231 in words is "six hundred fifty-six million, five hundred forty-three thousand, two hundred thirty-one".