21088328 has 16 divisors (see below), whose sum is σ = 41622000. Its totient is φ = 9989136.

The previous prime is 21088321. The next prime is 21088337. The reversal of 21088328 is 82388012.

It is a junction number, because it is equal to n+sod(n) for n = 21088294 and 21088303.

It is not an unprimeable number, because it can be changed into a prime (21088321) 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, 69218 + ... + 69521.

It is an arithmetic number, because the mean of its divisors is an integer number (2601375).

Almost surely, 2^21088328 is an apocalyptic number.

It is an amenable number.

21088328 is a deficient number, since it is larger than the sum of its proper divisors (20533672).

21088328 is a wasteful number, since it uses less digits than its factorization.

21088328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138764 (or 138760 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 32.

The square root of 21088328 is about 4592.2029571873. The cubic root of 21088328 is about 276.2786865100.

The spelling of 21088328 in words is "twenty-one million, eighty-eight thousand, three hundred twenty-eight".