21821452 has 12 divisors (see below), whose sum is σ = 38711176. Its totient is φ = 10761120.

The previous prime is 21821441. The next prime is 21821461. The reversal of 21821452 is 25412812.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37074 + ... + 37657.

Almost surely, 2^21821452 is an apocalyptic number.

It is an amenable number.

21821452 is a deficient number, since it is larger than the sum of its proper divisors (16889724).

21821452 is a wasteful number, since it uses less digits than its factorization.

21821452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74808 (or 74806 counting only the distinct ones).

The product of its digits is 1280, while the sum is 25.

The square root of 21821452 is about 4671.3437039036. The cubic root of 21821452 is about 279.4438450383.

The spelling of 21821452 in words is "twenty-one million, eight hundred twenty-one thousand, four hundred fifty-two".