18656351657 has 2 divisors, whose sum is σ = 18656351658. Its totient is φ = 18656351656.

The previous prime is 18656351621. The next prime is 18656351663. The reversal of 18656351657 is 75615365681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17435617936 + 1220733721 = 132044^2 + 34939^2 .

It is a cyclic number.

It is not a de Polignac number, because 18656351657 - 2¹² = 18656347561 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18656351599 and 18656351608.

It is not a weakly prime, because it can be changed into another prime (18656351687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9328175828 + 9328175829.

It is an arithmetic number, because the mean of its divisors is an integer number (9328175829).

Almost surely, 2^18656351657 is an apocalyptic number.

It is an amenable number.

18656351657 is a deficient number, since it is larger than the sum of its proper divisors (1).

18656351657 is an equidigital number, since it uses as much as digits as its factorization.

18656351657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4536000, while the sum is 53.

The spelling of 18656351657 in words is "eighteen billion, six hundred fifty-six million, three hundred fifty-one thousand, six hundred fifty-seven".