18924219121 has 2 divisors, whose sum is σ = 18924219122. Its totient is φ = 18924219120.

The previous prime is 18924219113. The next prime is 18924219169. The reversal of 18924219121 is 12191242981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18906250000 + 17969121 = 137500^2 + 4239^2 .

It is a cyclic number.

It is not a de Polignac number, because 18924219121 - 2³ = 18924219113 is a prime.

It is not a weakly prime, because it can be changed into another prime (18924211121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9462109560 + 9462109561.

It is an arithmetic number, because the mean of its divisors is an integer number (9462109561).

Almost surely, 2^18924219121 is an apocalyptic number.

It is an amenable number.

18924219121 is a deficient number, since it is larger than the sum of its proper divisors (1).

18924219121 is an equidigital number, since it uses as much as digits as its factorization.

18924219121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 40.

The spelling of 18924219121 in words is "eighteen billion, nine hundred twenty-four million, two hundred nineteen thousand, one hundred twenty-one".