21121922 has 16 divisors (see below), whose sum is σ = 33653880. Its totient is φ = 9907968.

The previous prime is 21121913. The next prime is 21121937. The reversal of 21121922 is 22912112.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 15452761 + 5669161 = 3931^2 + 2381^2 .

It is a super-3 number, since 3×21121922³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 21121894 and 21121903.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12428 + ... + 14024.

Almost surely, 2^21121922 is an apocalyptic number.

21121922 is a deficient number, since it is larger than the sum of its proper divisors (12531958).

21121922 is a wasteful number, since it uses less digits than its factorization.

21121922 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2005.

The product of its digits is 144, while the sum is 20.

The square root of 21121922 is about 4595.8592232574. The cubic root of 21121922 is about 276.4253139420.

The spelling of 21121922 in words is "twenty-one million, one hundred twenty-one thousand, nine hundred twenty-two".