21120688 has 20 divisors (see below), whose sum is σ = 41046480. Its totient is φ = 10528064.

The previous prime is 21120677. The next prime is 21120689. The reversal of 21120688 is 88602112.

It is not an unprimeable number, because it can be changed into a prime (21120689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3906 + ... + 7582.

It is an arithmetic number, because the mean of its divisors is an integer number (2052324).

Almost surely, 2^21120688 is an apocalyptic number.

It is an amenable number.

21120688 is a deficient number, since it is larger than the sum of its proper divisors (19925792).

21120688 is a wasteful number, since it uses less digits than its factorization.

21120688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4044 (or 4038 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 21120688 is about 4595.7249700129. The cubic root of 21120688 is about 276.4199306648.

The spelling of 21120688 in words is "twenty-one million, one hundred twenty thousand, six hundred eighty-eight".