18451748657 has 2 divisors, whose sum is σ = 18451748658. Its totient is φ = 18451748656.

The previous prime is 18451748639. The next prime is 18451748699. The reversal of 18451748657 is 75684715481.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17946353296 + 505395361 = 133964^2 + 22481^2 .

It is a cyclic number.

It is not a de Polignac number, because 18451748657 - 2¹² = 18451744561 is a prime.

It is a super-2 number, since 2×18451748657² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18451748257) 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, 9225874328 + 9225874329.

It is an arithmetic number, because the mean of its divisors is an integer number (9225874329).

Almost surely, 2^18451748657 is an apocalyptic number.

It is an amenable number.

18451748657 is a deficient number, since it is larger than the sum of its proper divisors (1).

18451748657 is an equidigital number, since it uses as much as digits as its factorization.

18451748657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7526400, while the sum is 56.

The spelling of 18451748657 in words is "eighteen billion, four hundred fifty-one million, seven hundred forty-eight thousand, six hundred fifty-seven".