657385879691 has 2 divisors, whose sum is σ = 657385879692. Its totient is φ = 657385879690.

The previous prime is 657385879607. The next prime is 657385879699. The reversal of 657385879691 is 196978583756.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 657385879691 - 2³⁰ = 656312137867 is a prime.

It is not a weakly prime, because it can be changed into another prime (657385879699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328692939845 + 328692939846.

It is an arithmetic number, because the mean of its divisors is an integer number (328692939846).

Almost surely, 2^657385879691 is an apocalyptic number.

657385879691 is a deficient number, since it is larger than the sum of its proper divisors (1).

657385879691 is an equidigital number, since it uses as much as digits as its factorization.

657385879691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 685843200, while the sum is 74.

The spelling of 657385879691 in words is "six hundred fifty-seven billion, three hundred eighty-five million, eight hundred seventy-nine thousand, six hundred ninety-one".