21488868 has 24 divisors (see below), whose sum is σ = 55712160. Its totient is φ = 7162920.

The previous prime is 21488839. The next prime is 21488881. The reversal of 21488868 is 86888412.

It is a happy number.

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 7 ways as a sum of consecutive naturals, for example, 99378 + ... + 99593.

It is an arithmetic number, because the mean of its divisors is an integer number (2321340).

Almost surely, 2^21488868 is an apocalyptic number.

It is an amenable number.

21488868 is an abundant number, since it is smaller than the sum of its proper divisors (34223292).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21488868 is a wasteful number, since it uses less digits than its factorization.

21488868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198984 (or 198976 counting only the distinct ones).

The product of its digits is 196608, while the sum is 45.

The square root of 21488868 is about 4635.6086978950. The cubic root of 21488868 is about 278.0168890590.

The spelling of 21488868 in words is "twenty-one million, four hundred eighty-eight thousand, eight hundred sixty-eight".