123606215657 has 2 divisors, whose sum is σ = 123606215658. Its totient is φ = 123606215656.

The previous prime is 123606215539. The next prime is 123606215669. The reversal of 123606215657 is 756512606321.

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., 118405498201 + 5200717456 = 344101^2 + 72116^2 .

It is a cyclic number.

It is not a de Polignac number, because 123606215657 - 2²⁶ = 123539106793 is a prime.

It is not a weakly prime, because it can be changed into another prime (123606415657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61803107828 + 61803107829.

It is an arithmetic number, because the mean of its divisors is an integer number (61803107829).

Almost surely, 2^123606215657 is an apocalyptic number.

It is an amenable number.

123606215657 is a deficient number, since it is larger than the sum of its proper divisors (1).

123606215657 is an equidigital number, since it uses as much as digits as its factorization.

123606215657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 453600, while the sum is 44.

The spelling of 123606215657 in words is "one hundred twenty-three billion, six hundred six million, two hundred fifteen thousand, six hundred fifty-seven".