18744615257 has 2 divisors, whose sum is σ = 18744615258. Its totient is φ = 18744615256.

The previous prime is 18744615193. The next prime is 18744615289. The reversal of 18744615257 is 75251644781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18262549321 + 482065936 = 135139^2 + 21956^2 .

It is a cyclic number.

It is not a de Polignac number, because 18744615257 - 2⁶ = 18744615193 is a prime.

It is a super-2 number, since 2×18744615257² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18744611257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9372307628 + 9372307629.

It is an arithmetic number, because the mean of its divisors is an integer number (9372307629).

Almost surely, 2^18744615257 is an apocalyptic number.

It is an amenable number.

18744615257 is a deficient number, since it is larger than the sum of its proper divisors (1).

18744615257 is an equidigital number, since it uses as much as digits as its factorization.

18744615257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1881600, while the sum is 50.

The spelling of 18744615257 in words is "eighteen billion, seven hundred forty-four million, six hundred fifteen thousand, two hundred fifty-seven".