21319788923 has 2 divisors, whose sum is σ = 21319788924. Its totient is φ = 21319788922.

The previous prime is 21319788887. The next prime is 21319788929. The reversal of 21319788923 is 32988791312.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21319788923 - 2²⁸ = 21051353467 is a prime.

It is not a weakly prime, because it can be changed into another prime (21319788929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10659894461 + 10659894462.

It is an arithmetic number, because the mean of its divisors is an integer number (10659894462).

Almost surely, 2^21319788923 is an apocalyptic number.

21319788923 is a deficient number, since it is larger than the sum of its proper divisors (1).

21319788923 is an equidigital number, since it uses as much as digits as its factorization.

21319788923 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1306368, while the sum is 53.

The spelling of 21319788923 in words is "twenty-one billion, three hundred nineteen million, seven hundred eighty-eight thousand, nine hundred twenty-three".