21234132 has 72 divisors (see below), whose sum is σ = 56609280. Its totient is φ = 6701760.

The previous prime is 21234127. The next prime is 21234137. The reversal of 21234132 is 23143212.

It is an interprime number because it is at equal distance from previous prime (21234127) and next prime (21234137).

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 (21234137) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 58969 + ... + 59327.

It is an arithmetic number, because the mean of its divisors is an integer number (786240).

Almost surely, 2^21234132 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 21234132, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28304640).

21234132 is an abundant number, since it is smaller than the sum of its proper divisors (35375148).

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

21234132 is a wasteful number, since it uses less digits than its factorization.

21234132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453 (or 448 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 21234132 is about 4608.0507809702. The cubic root of 21234132 is about 276.9139519073.

Adding to 21234132 its reverse (23143212), we get a palindrome (44377344).

The spelling of 21234132 in words is "twenty-one million, two hundred thirty-four thousand, one hundred thirty-two".