18697098809 has 2 divisors, whose sum is σ = 18697098810. Its totient is φ = 18697098808.

The previous prime is 18697098743. The next prime is 18697098817. The reversal of 18697098809 is 90889079681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11577114409 + 7119984400 = 107597^2 + 84380^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18697098809 is a prime.

It is not a weakly prime, because it can be changed into another prime (18697098829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9348549404 + 9348549405.

It is an arithmetic number, because the mean of its divisors is an integer number (9348549405).

Almost surely, 2^18697098809 is an apocalyptic number.

It is an amenable number.

18697098809 is a deficient number, since it is larger than the sum of its proper divisors (1).

18697098809 is an equidigital number, since it uses as much as digits as its factorization.

18697098809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15676416, while the sum is 65.

The spelling of 18697098809 in words is "eighteen billion, six hundred ninety-seven million, ninety-eight thousand, eight hundred nine".