656649613 has 2 divisors, whose sum is σ = 656649614. Its totient is φ = 656649612.

The previous prime is 656649601. The next prime is 656649629. The reversal of 656649613 is 316946656.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 382515364 + 274134249 = 19558^2 + 16557^2 .

It is a cyclic number.

It is not a de Polignac number, because 656649613 - 2²¹ = 654552461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (656649013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328324806 + 328324807.

It is an arithmetic number, because the mean of its divisors is an integer number (328324807).

Almost surely, 2^656649613 is an apocalyptic number.

It is an amenable number.

656649613 is a deficient number, since it is larger than the sum of its proper divisors (1).

656649613 is an equidigital number, since it uses as much as digits as its factorization.

656649613 is an evil number, because the sum of its binary digits is even.

The product of its digits is 699840, while the sum is 46.

The square root of 656649613 is about 25625.1753750096. The cubic root of 656649613 is about 869.1830146922.

The spelling of 656649613 in words is "six hundred fifty-six million, six hundred forty-nine thousand, six hundred thirteen".