21242232 has 48 divisors (see below), whose sum is σ = 62763480. Its totient is φ = 6436800.

The previous prime is 21242203. The next prime is 21242237. The reversal of 21242232 is 23224212.

21242232 is a `hidden beast` number, since 212 + 422 + 32 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21242237) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12619 + ... + 14202.

Almost surely, 2^21242232 is an apocalyptic number.

21242232 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21242232 is an abundant number, since it is smaller than the sum of its proper divisors (41521248).

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

21242232 is a wasteful number, since it uses less digits than its factorization.

21242232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26844 (or 26837 counting only the distinct ones).

The product of its digits is 384, while the sum is 18.

The square root of 21242232 is about 4608.9295937343. The cubic root of 21242232 is about 276.9491580849.

Adding to 21242232 its reverse (23224212), we get a palindrome (44466444).

It can be divided in two parts, 2124 and 2232, that added together give a square (4356 = 66²).

The spelling of 21242232 in words is "twenty-one million, two hundred forty-two thousand, two hundred thirty-two".