21624269 has 2 divisors, whose sum is σ = 21624270. Its totient is φ = 21624268.

The previous prime is 21624263. The next prime is 21624287. The reversal of 21624269 is 96242612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21501769 + 122500 = 4637^2 + 350^2 .

It is a cyclic number.

It is not a de Polignac number, because 21624269 - 2⁸ = 21624013 is a prime.

It is a super-2 number, since 2×21624269² = 935218019568722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21624263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10812134 + 10812135.

It is an arithmetic number, because the mean of its divisors is an integer number (10812135).

Almost surely, 2^21624269 is an apocalyptic number.

It is an amenable number.

21624269 is a deficient number, since it is larger than the sum of its proper divisors (1).

21624269 is an equidigital number, since it uses as much as digits as its factorization.

21624269 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10368, while the sum is 32.

The square root of 21624269 is about 4650.1902111634. The cubic root of 21624269 is about 278.5995934956.

The spelling of 21624269 in words is "twenty-one million, six hundred twenty-four thousand, two hundred sixty-nine".