21322144 has 24 divisors (see below), whose sum is σ = 42370020. Its totient is φ = 10561536.

The previous prime is 21322139. The next prime is 21322181. The reversal of 21322144 is 44122312.

It can be written as a sum of positive squares in 2 ways, for example, as 20976400 + 345744 = 4580^2 + 588^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 432 + ... + 6544.

Almost surely, 2^21322144 is an apocalyptic number.

It is an amenable number.

21322144 is a deficient number, since it is larger than the sum of its proper divisors (21047876).

21322144 is a wasteful number, since it uses less digits than its factorization.

21322144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6232 (or 6224 counting only the distinct ones).

The product of its digits is 384, while the sum is 19.

The square root of 21322144 is about 4617.5907137814. The cubic root of 21322144 is about 277.2960121952.

Adding to 21322144 its reverse (44122312), we get a palindrome (65444456).

The spelling of 21322144 in words is "twenty-one million, three hundred twenty-two thousand, one hundred forty-four".