21622459 has 2 divisors, whose sum is σ = 21622460. Its totient is φ = 21622458.

The previous prime is 21622427. The next prime is 21622501. The reversal of 21622459 is 95422612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21622459 - 2⁵ = 21622427 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21622459.

It is not a weakly prime, because it can be changed into another prime (21622259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10811229 + 10811230.

It is an arithmetic number, because the mean of its divisors is an integer number (10811230).

Almost surely, 2^21622459 is an apocalyptic number.

21622459 is a deficient number, since it is larger than the sum of its proper divisors (1).

21622459 is an equidigital number, since it uses as much as digits as its factorization.

21622459 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8640, while the sum is 31.

The square root of 21622459 is about 4649.9955913958. The cubic root of 21622459 is about 278.5918201409.

The spelling of 21622459 in words is "twenty-one million, six hundred twenty-two thousand, four hundred fifty-nine".