21732432 has 20 divisors (see below), whose sum is σ = 56142240. Its totient is φ = 7244128.

The previous prime is 21732413. The next prime is 21732437. The reversal of 21732432 is 23423712.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21732437) 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, 226332 + ... + 226427.

It is an arithmetic number, because the mean of its divisors is an integer number (2807112).

Almost surely, 2^21732432 is an apocalyptic number.

It is an amenable number.

21732432 is an abundant number, since it is smaller than the sum of its proper divisors (34409808).

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

21732432 is a wasteful number, since it uses less digits than its factorization.

21732432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 452770 (or 452764 counting only the distinct ones).

The product of its digits is 2016, while the sum is 24.

The square root of 21732432 is about 4661.8056587550. The cubic root of 21732432 is about 279.0633327018.

The spelling of 21732432 in words is "twenty-one million, seven hundred thirty-two thousand, four hundred thirty-two".