18949399369 has 2 divisors, whose sum is σ = 18949399370. Its totient is φ = 18949399368.

The previous prime is 18949399303. The next prime is 18949399397. The reversal of 18949399369 is 96399394981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12235235769 + 6714163600 = 110613^2 + 81940^2 .

It is an emirp because it is prime and its reverse (96399394981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18949399369 - 2⁷ = 18949399241 is a prime.

It is a super-2 number, since 2×18949399369² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18949399298 and 18949399307.

It is not a weakly prime, because it can be changed into another prime (18949399769) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9474699684 + 9474699685.

It is an arithmetic number, because the mean of its divisors is an integer number (9474699685).

Almost surely, 2^18949399369 is an apocalyptic number.

It is an amenable number.

18949399369 is a deficient number, since it is larger than the sum of its proper divisors (1).

18949399369 is an equidigital number, since it uses as much as digits as its factorization.

18949399369 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 102036672, while the sum is 70.

The spelling of 18949399369 in words is "eighteen billion, nine hundred forty-nine million, three hundred ninety-nine thousand, three hundred sixty-nine".