21274288 has 20 divisors (see below), whose sum is σ = 47107600. Its totient is φ = 9117504.

The previous prime is 21274283. The next prime is 21274289. The reversal of 21274288 is 88247212.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (21274283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 94863 + ... + 95086.

It is an arithmetic number, because the mean of its divisors is an integer number (2355380).

Almost surely, 2^21274288 is an apocalyptic number.

21274288 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21274288 is an abundant number, since it is smaller than the sum of its proper divisors (25833312).

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

21274288 is a wasteful number, since it uses less digits than its factorization.

21274288 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189964 (or 189958 counting only the distinct ones).

The product of its digits is 14336, while the sum is 34.

The square root of 21274288 is about 4612.4058797985. The cubic root of 21274288 is about 277.0883998898.

The spelling of 21274288 in words is "twenty-one million, two hundred seventy-four thousand, two hundred eighty-eight".