18408940619 has 2 divisors, whose sum is σ = 18408940620. Its totient is φ = 18408940618.

The previous prime is 18408940549. The next prime is 18408940651. The reversal of 18408940619 is 91604980481.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18408940619 is a prime.

It is a super-2 number, since 2×18408940619² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (18408940819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9204470309 + 9204470310.

It is an arithmetic number, because the mean of its divisors is an integer number (9204470310).

Almost surely, 2^18408940619 is an apocalyptic number.

18408940619 is a deficient number, since it is larger than the sum of its proper divisors (1).

18408940619 is an equidigital number, since it uses as much as digits as its factorization.

18408940619 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 497664, while the sum is 50.

The spelling of 18408940619 in words is "eighteen billion, four hundred eight million, nine hundred forty thousand, six hundred nineteen".