656138597 has 2 divisors, whose sum is σ = 656138598. Its totient is φ = 656138596.

The previous prime is 656138573. The next prime is 656138599. The reversal of 656138597 is 795831656.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 331021636 + 325116961 = 18194^2 + 18031^2 .

It is a cyclic number.

It is not a de Polignac number, because 656138597 - 2²⁶ = 589029733 is a prime.

Together with 656138599, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (656138599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328069298 + 328069299.

It is an arithmetic number, because the mean of its divisors is an integer number (328069299).

Almost surely, 2^656138597 is an apocalyptic number.

It is an amenable number.

656138597 is a deficient number, since it is larger than the sum of its proper divisors (1).

656138597 is an equidigital number, since it uses as much as digits as its factorization.

656138597 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1360800, while the sum is 50.

The square root of 656138597 is about 25615.2024586963. The cubic root of 656138597 is about 868.9574851314.

The spelling of 656138597 in words is "six hundred fifty-six million, one hundred thirty-eight thousand, five hundred ninety-seven".