21889223 has 2 divisors, whose sum is σ = 21889224. Its totient is φ = 21889222.

The previous prime is 21889207. The next prime is 21889247. The reversal of 21889223 is 32298812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21889223 - 2⁴ = 21889207 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21889823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10944611 + 10944612.

It is an arithmetic number, because the mean of its divisors is an integer number (10944612).

Almost surely, 2^21889223 is an apocalyptic number.

21889223 is a deficient number, since it is larger than the sum of its proper divisors (1).

21889223 is an equidigital number, since it uses as much as digits as its factorization.

21889223 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13824, while the sum is 35.

The square root of 21889223 is about 4678.5919890497. The cubic root of 21889223 is about 279.7328361513.

It can be divided in two parts, 2188 and 9223, that added together give a palindrome (11411).

The spelling of 21889223 in words is "twenty-one million, eight hundred eighty-nine thousand, two hundred twenty-three".