21044688 has 40 divisors (see below), whose sum is σ = 62132928. Its totient is φ = 6012672.

The previous prime is 21044687. The next prime is 21044711. The reversal of 21044688 is 88644012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21044687) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30981 + ... + 31652.

Almost surely, 2^21044688 is an apocalyptic number.

21044688 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21044688 is an abundant number, since it is smaller than the sum of its proper divisors (41088240).

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

21044688 is a wasteful number, since it uses less digits than its factorization.

21044688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62651 (or 62645 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 33.

The square root of 21044688 is about 4587.4489642938. The cubic root of 21044688 is about 276.0879786739.

The spelling of 21044688 in words is "twenty-one million, forty-four thousand, six hundred eighty-eight".