21233579 has 2 divisors, whose sum is σ = 21233580. Its totient is φ = 21233578.

The previous prime is 21233503. The next prime is 21233587. The reversal of 21233579 is 97533212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21233579 - 2²⁰ = 20185003 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21233599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10616789 + 10616790.

It is an arithmetic number, because the mean of its divisors is an integer number (10616790).

Almost surely, 2^21233579 is an apocalyptic number.

21233579 is a deficient number, since it is larger than the sum of its proper divisors (1).

21233579 is an equidigital number, since it uses as much as digits as its factorization.

21233579 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11340, while the sum is 32.

The square root of 21233579 is about 4607.9907769005. The cubic root of 21233579 is about 276.9115479986.

It can be divided in two parts, 21233 and 579, that added together give a palindrome (21812).

The spelling of 21233579 in words is "twenty-one million, two hundred thirty-three thousand, five hundred seventy-nine".