18665490797 has 2 divisors, whose sum is σ = 18665490798. Its totient is φ = 18665490796.

The previous prime is 18665490791. The next prime is 18665490839. The reversal of 18665490797 is 79709456681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13691574121 + 4973916676 = 117011^2 + 70526^2 .

It is a cyclic number.

It is not a de Polignac number, because 18665490797 - 2⁶ = 18665490733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18665490791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9332745398 + 9332745399.

It is an arithmetic number, because the mean of its divisors is an integer number (9332745399).

Almost surely, 2^18665490797 is an apocalyptic number.

It is an amenable number.

18665490797 is a deficient number, since it is larger than the sum of its proper divisors (1).

18665490797 is an equidigital number, since it uses as much as digits as its factorization.

18665490797 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 22861440, while the sum is 62.

The spelling of 18665490797 in words is "eighteen billion, six hundred sixty-five million, four hundred ninety thousand, seven hundred ninety-seven".