21220323 has 4 divisors (see below), whose sum is σ = 28293768. Its totient is φ = 14146880.

The previous prime is 21220319. The next prime is 21220327. The reversal of 21220323 is 32302212.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21220319) and next prime (21220327).

It is a cyclic number.

It is not a de Polignac number, because 21220323 - 2² = 21220319 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21220327) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3536718 + ... + 3536723.

It is an arithmetic number, because the mean of its divisors is an integer number (7073442).

Almost surely, 2^21220323 is an apocalyptic number.

21220323 is a deficient number, since it is larger than the sum of its proper divisors (7073445).

21220323 is an equidigital number, since it uses as much as digits as its factorization.

21220323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7073444.

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 21220323 is about 4606.5521814042. The cubic root of 21220323 is about 276.8539112460.

Adding to 21220323 its reverse (32302212), we get a palindrome (53522535).

It can be divided in two parts, 212203 and 23, that added together give a triangular number (212226 = T₆₅₁).

The spelling of 21220323 in words is "twenty-one million, two hundred twenty thousand, three hundred twenty-three".