21223159 has 2 divisors, whose sum is σ = 21223160. Its totient is φ = 21223158.

The previous prime is 21223141. The next prime is 21223187. The reversal of 21223159 is 95132212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21223159 - 2¹⁹ = 20698871 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21220159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611579 + 10611580.

It is an arithmetic number, because the mean of its divisors is an integer number (10611580).

Almost surely, 2^21223159 is an apocalyptic number.

21223159 is a deficient number, since it is larger than the sum of its proper divisors (1).

21223159 is an equidigital number, since it uses as much as digits as its factorization.

21223159 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1080, while the sum is 25.

The square root of 21223159 is about 4606.8599935314. The cubic root of 21223159 is about 276.8662441201.

The spelling of 21223159 in words is "twenty-one million, two hundred twenty-three thousand, one hundred fifty-nine".