21331322 has 4 divisors (see below), whose sum is σ = 31996986. Its totient is φ = 10665660.

The previous prime is 21331313. The next prime is 21331333. The reversal of 21331322 is 22313312.

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

It can be written as a sum of positive squares in only one way, i.e., 17986081 + 3345241 = 4241^2 + 1829^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21331322.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5332829 + ... + 5332832.

Almost surely, 2^21331322 is an apocalyptic number.

21331322 is a deficient number, since it is larger than the sum of its proper divisors (10665664).

21331322 is a wasteful number, since it uses less digits than its factorization.

21331322 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10665663.

The product of its digits is 216, while the sum is 17.

The square root of 21331322 is about 4618.5844151645. The cubic root of 21331322 is about 277.3357933373.

Adding to 21331322 its reverse (22313312), we get a palindrome (43644634).

The spelling of 21331322 in words is "twenty-one million, three hundred thirty-one thousand, three hundred twenty-two".