21422232 has 80 divisors (see below), whose sum is σ = 64643040. Its totient is φ = 6588864.

The previous prime is 21422231. The next prime is 21422273. The reversal of 21422232 is 23222412.

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 (21422231) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 7153 + ... + 9695.

It is an arithmetic number, because the mean of its divisors is an integer number (808038).

Almost surely, 2^21422232 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21422232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32321520).

21422232 is an abundant number, since it is smaller than the sum of its proper divisors (43220808).

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

21422232 is a wasteful number, since it uses less digits than its factorization.

21422232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2574 (or 2561 counting only the distinct ones).

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

The square root of 21422232 is about 4628.4157116664. The cubic root of 21422232 is about 277.7292189370.

Adding to 21422232 its reverse (23222412), we get a palindrome (44644644).

The spelling of 21422232 in words is "twenty-one million, four hundred twenty-two thousand, two hundred thirty-two".