21552868 has 12 divisors (see below), whose sum is σ = 37869552. Its totient is φ = 10733000.

The previous prime is 21552851. The next prime is 21552893. The reversal of 21552868 is 86825512.

It is a super-2 number, since 2×21552868² = 929052238050848, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9730 + ... + 11737.

It is an arithmetic number, because the mean of its divisors is an integer number (3155796).

Almost surely, 2^21552868 is an apocalyptic number.

It is an amenable number.

21552868 is a deficient number, since it is larger than the sum of its proper divisors (16316684).

21552868 is a wasteful number, since it uses less digits than its factorization.

21552868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21722 (or 21720 counting only the distinct ones).

The product of its digits is 38400, while the sum is 37.

The square root of 21552868 is about 4642.5066505068. The cubic root of 21552868 is about 278.2926201301.

The spelling of 21552868 in words is "twenty-one million, five hundred fifty-two thousand, eight hundred sixty-eight".