21267888 has 40 divisors (see below), whose sum is σ = 55109568. Its totient is φ = 7067712.

The previous prime is 21267887. The next prime is 21267899. The reversal of 21267888 is 88876212.

It is not an unprimeable number, because it can be changed into a prime (21267881) 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, 26631 + ... + 27417.

Almost surely, 2^21267888 is an apocalyptic number.

It is an amenable number.

21267888 is an abundant number, since it is smaller than the sum of its proper divisors (33841680).

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

21267888 is a wasteful number, since it uses less digits than its factorization.

21267888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1361 (or 1355 counting only the distinct ones).

The product of its digits is 86016, while the sum is 42.

The square root of 21267888 is about 4611.7120465181. The cubic root of 21267888 is about 277.0606113590.

It can be divided in two parts, 21267 and 888, that added together give a triangular number (22155 = T₂₁₀).

The spelling of 21267888 in words is "twenty-one million, two hundred sixty-seven thousand, eight hundred eighty-eight".