18821044999 has 2 divisors, whose sum is σ = 18821045000. Its totient is φ = 18821044998.

The previous prime is 18821044937. The next prime is 18821045059. The reversal of 18821044999 is 99944012881.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18821044999 - 2³¹ = 16673561351 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18821044499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9410522499 + 9410522500.

It is an arithmetic number, because the mean of its divisors is an integer number (9410522500).

Almost surely, 2^18821044999 is an apocalyptic number.

18821044999 is a deficient number, since it is larger than the sum of its proper divisors (1).

18821044999 is an equidigital number, since it uses as much as digits as its factorization.

18821044999 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1492992, while the sum is 55.

The spelling of 18821044999 in words is "eighteen billion, eight hundred twenty-one million, forty-four thousand, nine hundred ninety-nine".