21927823 has 2 divisors, whose sum is σ = 21927824. Its totient is φ = 21927822.

The previous prime is 21927817. The next prime is 21927833. The reversal of 21927823 is 32872912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21927823 - 2¹³ = 21919631 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21927833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10963911 + 10963912.

It is an arithmetic number, because the mean of its divisors is an integer number (10963912).

Almost surely, 2^21927823 is an apocalyptic number.

21927823 is a deficient number, since it is larger than the sum of its proper divisors (1).

21927823 is an equidigital number, since it uses as much as digits as its factorization.

21927823 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 34.

The square root of 21927823 is about 4682.7153447546. The cubic root of 21927823 is about 279.8971688721.

The spelling of 21927823 in words is "twenty-one million, nine hundred twenty-seven thousand, eight hundred twenty-three".