18158655217 has 2 divisors, whose sum is σ = 18158655218. Its totient is φ = 18158655216.

The previous prime is 18158655157. The next prime is 18158655223. The reversal of 18158655217 is 71255685181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13820588721 + 4338066496 = 117561^2 + 65864^2 .

It is a cyclic number.

It is not a de Polignac number, because 18158655217 - 2²³ = 18150266609 is a prime.

It is not a weakly prime, because it can be changed into another prime (18158659217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9079327608 + 9079327609.

It is an arithmetic number, because the mean of its divisors is an integer number (9079327609).

Almost surely, 2^18158655217 is an apocalyptic number.

It is an amenable number.

18158655217 is a deficient number, since it is larger than the sum of its proper divisors (1).

18158655217 is an equidigital number, since it uses as much as digits as its factorization.

18158655217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 672000, while the sum is 49.

The spelling of 18158655217 in words is "eighteen billion, one hundred fifty-eight million, six hundred fifty-five thousand, two hundred seventeen".