21889927 has 2 divisors, whose sum is σ = 21889928. Its totient is φ = 21889926.

The previous prime is 21889909. The next prime is 21889943. The reversal of 21889927 is 72998812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21889927 - 2⁷ = 21889799 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21889327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10944963 + 10944964.

It is an arithmetic number, because the mean of its divisors is an integer number (10944964).

Almost surely, 2^21889927 is an apocalyptic number.

21889927 is a deficient number, since it is larger than the sum of its proper divisors (1).

21889927 is an equidigital number, since it uses as much as digits as its factorization.

21889927 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145152, while the sum is 46.

The square root of 21889927 is about 4678.6672247554. The cubic root of 21889927 is about 279.7358350366.

The spelling of 21889927 in words is "twenty-one million, eight hundred eighty-nine thousand, nine hundred twenty-seven".