656721113 has 2 divisors, whose sum is σ = 656721114. Its totient is φ = 656721112.

The previous prime is 656721053. The next prime is 656721127. The reversal of 656721113 is 311127656.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 403688464 + 253032649 = 20092^2 + 15907^2 .

It is a cyclic number.

It is not a de Polignac number, because 656721113 - 2⁶ = 656721049 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 656721113.

It is not a weakly prime, because it can be changed into another prime (656721133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328360556 + 328360557.

It is an arithmetic number, because the mean of its divisors is an integer number (328360557).

Almost surely, 2^656721113 is an apocalyptic number.

It is an amenable number.

656721113 is a deficient number, since it is larger than the sum of its proper divisors (1).

656721113 is an equidigital number, since it uses as much as digits as its factorization.

656721113 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7560, while the sum is 32.

The square root of 656721113 is about 25626.5704494378. The cubic root of 656721113 is about 869.2145608567.

Adding to 656721113 its reverse (311127656), we get a palindrome (967848769).

The spelling of 656721113 in words is "six hundred fifty-six million, seven hundred twenty-one thousand, one hundred thirteen".