21252323 has 2 divisors, whose sum is σ = 21252324. Its totient is φ = 21252322.

The previous prime is 21252293. The next prime is 21252337. The reversal of 21252323 is 32325212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21252323 - 2¹⁰ = 21251299 is a prime.

It is a super-2 number, since 2×21252323² = 903322465792658, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 21252295 and 21252304.

It is not a weakly prime, because it can be changed into another prime (21252353) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10626161 + 10626162.

It is an arithmetic number, because the mean of its divisors is an integer number (10626162).

Almost surely, 2^21252323 is an apocalyptic number.

21252323 is a deficient number, since it is larger than the sum of its proper divisors (1).

21252323 is an equidigital number, since it uses as much as digits as its factorization.

21252323 is an evil number, because the sum of its binary digits is even.

The product of its digits is 720, while the sum is 20.

The square root of 21252323 is about 4610.0241864875. The cubic root of 21252323 is about 276.9930055101.

Adding to 21252323 its reverse (32325212), we get a palindrome (53577535).

The spelling of 21252323 in words is "twenty-one million, two hundred fifty-two thousand, three hundred twenty-three".