656571556117 has 2 divisors, whose sum is σ = 656571556118. Its totient is φ = 656571556116.

The previous prime is 656571556079. The next prime is 656571556133. The reversal of 656571556117 is 711655175656.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 404478192196 + 252093363921 = 635986^2 + 502089^2 .

It is a cyclic number.

It is not a de Polignac number, because 656571556117 - 2⁷ = 656571555989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (656571556217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328285778058 + 328285778059.

It is an arithmetic number, because the mean of its divisors is an integer number (328285778059).

Almost surely, 2^656571556117 is an apocalyptic number.

It is an amenable number.

656571556117 is a deficient number, since it is larger than the sum of its proper divisors (1).

656571556117 is an equidigital number, since it uses as much as digits as its factorization.

656571556117 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6615000, while the sum is 55.

The spelling of 656571556117 in words is "six hundred fifty-six billion, five hundred seventy-one million, five hundred fifty-six thousand, one hundred seventeen".