656313643 has 2 divisors, whose sum is σ = 656313644. Its totient is φ = 656313642.

The previous prime is 656313629. The next prime is 656313661. The reversal of 656313643 is 346313656.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-656313643 is a prime.

It is not a weakly prime, because it can be changed into another prime (656313683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328156821 + 328156822.

It is an arithmetic number, because the mean of its divisors is an integer number (328156822).

Almost surely, 2^656313643 is an apocalyptic number.

656313643 is a deficient number, since it is larger than the sum of its proper divisors (1).

656313643 is an equidigital number, since it uses as much as digits as its factorization.

656313643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 116640, while the sum is 37.

The square root of 656313643 is about 25618.6190689506. The cubic root of 656313643 is about 869.0347523470.

The spelling of 656313643 in words is "six hundred fifty-six million, three hundred thirteen thousand, six hundred forty-three".