21921476 has 12 divisors (see below), whose sum is σ = 38621100. Its totient is φ = 10886880.

The previous prime is 21921469. The next prime is 21921481. The reversal of 21921476 is 67412912.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1000000 + 20921476 = 1000^2 + 4574^2 .

It is a super-2 number, since 2×21921476² = 961102220037152, which contains 22 as substring.

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, 17795 + ... + 18986.

It is an arithmetic number, because the mean of its divisors is an integer number (3218425).

Almost surely, 2^21921476 is an apocalyptic number.

It is an amenable number.

21921476 is a deficient number, since it is larger than the sum of its proper divisors (16699624).

21921476 is a wasteful number, since it uses less digits than its factorization.

21921476 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36934 (or 36932 counting only the distinct ones).

The product of its digits is 6048, while the sum is 32.

The square root of 21921476 is about 4682.0375906223. The cubic root of 21921476 is about 279.8701608899.

The spelling of 21921476 in words is "twenty-one million, nine hundred twenty-one thousand, four hundred seventy-six".