21127888 has 40 divisors (see below), whose sum is σ = 42620040. Its totient is φ = 10137600.

The previous prime is 21127877. The next prime is 21127901. The reversal of 21127888 is 88872112.

It can be written as a sum of positive squares in 4 ways, for example, as 10810944 + 10316944 = 3288^2 + 3212^2 .

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a congruent number.

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, 52488 + ... + 52888.

It is an arithmetic number, because the mean of its divisors is an integer number (1065501).

Almost surely, 2^21127888 is an apocalyptic number.

It is an amenable number.

21127888 is an abundant number, since it is smaller than the sum of its proper divisors (21492152).

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

21127888 is a wasteful number, since it uses less digits than its factorization.

21127888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 535 (or 529 counting only the distinct ones).

The product of its digits is 14336, while the sum is 37.

The square root of 21127888 is about 4596.5082399578. The cubic root of 21127888 is about 276.4513374288.

It can be divided in two parts, 2112 and 7888, that added together give a 4-th power (10000 = 10⁴).

The spelling of 21127888 in words is "twenty-one million, one hundred twenty-seven thousand, eight hundred eighty-eight".