18240993569 has 2 divisors, whose sum is σ = 18240993570. Its totient is φ = 18240993568.

The previous prime is 18240993559. The next prime is 18240993583. The reversal of 18240993569 is 96539904281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17639027344 + 601966225 = 132812^2 + 24535^2 .

It is a cyclic number.

It is not a de Polignac number, because 18240993569 - 2⁸ = 18240993313 is a prime.

It is a super-2 number, since 2×18240993569² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18240993509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9120496784 + 9120496785.

It is an arithmetic number, because the mean of its divisors is an integer number (9120496785).

Almost surely, 2^18240993569 is an apocalyptic number.

It is an amenable number.

18240993569 is a deficient number, since it is larger than the sum of its proper divisors (1).

18240993569 is an equidigital number, since it uses as much as digits as its factorization.

18240993569 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4199040, while the sum is 56.

The spelling of 18240993569 in words is "eighteen billion, two hundred forty million, nine hundred ninety-three thousand, five hundred sixty-nine".