21000311323 has 2 divisors, whose sum is σ = 21000311324. Its totient is φ = 21000311322.

The previous prime is 21000311303. The next prime is 21000311341. The reversal of 21000311323 is 32311300012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21000311323 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21000311297 and 21000311306.

It is not a weakly prime, because it can be changed into another prime (21000311303) 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, 10500155661 + 10500155662.

It is an arithmetic number, because the mean of its divisors is an integer number (10500155662).

Almost surely, 2^21000311323 is an apocalyptic number.

21000311323 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000311323 is an equidigital number, since it uses as much as digits as its factorization.

21000311323 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108, while the sum is 16.

Adding to 21000311323 its reverse (32311300012), we get a palindrome (53311611335).

The spelling of 21000311323 in words is "twenty-one billion, three hundred eleven thousand, three hundred twenty-three".