21323711 has 2 divisors, whose sum is σ = 21323712. Its totient is φ = 21323710.

The previous prime is 21323707. The next prime is 21323713. The reversal of 21323711 is 11732312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21323711 - 2² = 21323707 is a prime.

Together with 21323713, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21323713) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10661855 + 10661856.

It is an arithmetic number, because the mean of its divisors is an integer number (10661856).

Almost surely, 2^21323711 is an apocalyptic number.

21323711 is a deficient number, since it is larger than the sum of its proper divisors (1).

21323711 is an equidigital number, since it uses as much as digits as its factorization.

21323711 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 252, while the sum is 20.

The square root of 21323711 is about 4617.7603878937. The cubic root of 21323711 is about 277.3028050112.

The spelling of 21323711 in words is "twenty-one million, three hundred twenty-three thousand, seven hundred eleven".