21804111907 has 2 divisors, whose sum is σ = 21804111908. Its totient is φ = 21804111906.

The previous prime is 21804111871. The next prime is 21804111911. The reversal of 21804111907 is 70911140812.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21804111907 is a prime.

It is not a weakly prime, because it can be changed into another prime (21804111977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10902055953 + 10902055954.

It is an arithmetic number, because the mean of its divisors is an integer number (10902055954).

Almost surely, 2^21804111907 is an apocalyptic number.

21804111907 is a deficient number, since it is larger than the sum of its proper divisors (1).

21804111907 is an equidigital number, since it uses as much as digits as its factorization.

21804111907 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4032, while the sum is 34.

The spelling of 21804111907 in words is "twenty-one billion, eight hundred four million, one hundred eleven thousand, nine hundred seven".