18397312876849 has 2 divisors, whose sum is σ = 18397312876850. Its totient is φ = 18397312876848.

The previous prime is 18397312876769. The next prime is 18397312876879. The reversal of 18397312876849 is 94867821379381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18291505798449 + 105807078400 = 4276857^2 + 325280^2 .

It is a cyclic number.

It is not a de Polignac number, because 18397312876849 - 2³³ = 18388722942257 is a prime.

It is a super-2 number, since 2×18397312876849² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18397312876879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9198656438424 + 9198656438425.

It is an arithmetic number, because the mean of its divisors is an integer number (9198656438425).

Almost surely, 2^{18397312876849} is an apocalyptic number.

It is an amenable number.

18397312876849 is a deficient number, since it is larger than the sum of its proper divisors (1).

18397312876849 is an equidigital number, since it uses as much as digits as its factorization.

18397312876849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 877879296, while the sum is 76.

The spelling of 18397312876849 in words is "eighteen trillion, three hundred ninety-seven billion, three hundred twelve million, eight hundred seventy-six thousand, eight hundred forty-nine".