18397395761 has 2 divisors, whose sum is σ = 18397395762. Its totient is φ = 18397395760.

The previous prime is 18397395743. The next prime is 18397395773. The reversal of 18397395761 is 16759379381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14358030625 + 4039365136 = 119825^2 + 63556^2 .

It is a cyclic number.

It is not a de Polignac number, because 18397395761 - 2³⁰ = 17323653937 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18397395761.

It is not a weakly prime, because it can be changed into another prime (18397395721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9198697880 + 9198697881.

It is an arithmetic number, because the mean of its divisors is an integer number (9198697881).

Almost surely, 2^18397395761 is an apocalyptic number.

It is an amenable number.

18397395761 is a deficient number, since it is larger than the sum of its proper divisors (1).

18397395761 is an equidigital number, since it uses as much as digits as its factorization.

18397395761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8573040, while the sum is 59.

The spelling of 18397395761 in words is "eighteen billion, three hundred ninety-seven million, three hundred ninety-five thousand, seven hundred sixty-one".