21923567 has 2 divisors, whose sum is σ = 21923568. Its totient is φ = 21923566.

The previous prime is 21923563. The next prime is 21923569. The reversal of 21923567 is 76532912.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21923567 - 2² = 21923563 is a prime.

Together with 21923569, 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 (21923563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10961783 + 10961784.

It is an arithmetic number, because the mean of its divisors is an integer number (10961784).

Almost surely, 2^21923567 is an apocalyptic number.

21923567 is a deficient number, since it is larger than the sum of its proper divisors (1).

21923567 is an equidigital number, since it uses as much as digits as its factorization.

21923567 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22680, while the sum is 35.

The square root of 21923567 is about 4682.2608855125. The cubic root of 21923567 is about 279.8790591639.

The spelling of 21923567 in words is "twenty-one million, nine hundred twenty-three thousand, five hundred sixty-seven".