21696288 has 48 divisors (see below), whose sum is σ = 57296736. Its totient is φ = 7188480.

The previous prime is 21696277. The next prime is 21696307. The reversal of 21696288 is 88269612.

It is a tau number, because it is divible by the number of its divisors (48).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17943 + ... + 19113.

It is an arithmetic number, because the mean of its divisors is an integer number (1193682).

Almost surely, 2^21696288 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21696288, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28648368).

21696288 is an abundant number, since it is smaller than the sum of its proper divisors (35600448).

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

21696288 is a wasteful number, since it uses less digits than its factorization.

21696288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1377 (or 1369 counting only the distinct ones).

The product of its digits is 82944, while the sum is 42.

The square root of 21696288 is about 4657.9274361029. The cubic root of 21696288 is about 278.9085400553.

The spelling of 21696288 in words is "twenty-one million, six hundred ninety-six thousand, two hundred eighty-eight".