21632472 has 48 divisors (see below), whose sum is σ = 59177040. Its totient is φ = 7138368.

The previous prime is 21632459. The next prime is 21632473. The reversal of 21632472 is 27423612.

21632472 is a `hidden beast` number, since 21 + 632 + 4 + 7 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21632473) 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 11 ways as a sum of consecutive naturals, for example, 5958 + ... + 8874.

It is an arithmetic number, because the mean of its divisors is an integer number (1232855).

Almost surely, 2^21632472 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 21632472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29588520).

21632472 is an abundant number, since it is smaller than the sum of its proper divisors (37544568).

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

21632472 is a wasteful number, since it uses less digits than its factorization.

21632472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3032 (or 3025 counting only the distinct ones).

The product of its digits is 4032, while the sum is 27.

The square root of 21632472 is about 4651.0721344653. The cubic root of 21632472 is about 278.6348172458.

The spelling of 21632472 in words is "twenty-one million, six hundred thirty-two thousand, four hundred seventy-two".