21579132 has 48 divisors (see below), whose sum is σ = 53020800. Its totient is φ = 6820800.

The previous prime is 21579127. The next prime is 21579143. The reversal of 21579132 is 23197512.

It is a self number, because there is not a number n which added to its sum of digits gives 21579132.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20007 + ... + 21057.

It is an arithmetic number, because the mean of its divisors is an integer number (1104600).

Almost surely, 2^21579132 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 21579132, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26510400).

21579132 is an abundant number, since it is smaller than the sum of its proper divisors (31441668).

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

21579132 is a wasteful number, since it uses less digits than its factorization.

21579132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1146 (or 1144 counting only the distinct ones).

The product of its digits is 3780, while the sum is 30.

The square root of 21579132 is about 4645.3344336011. The cubic root of 21579132 is about 278.4056153082.

The spelling of 21579132 in words is "twenty-one million, five hundred seventy-nine thousand, one hundred thirty-two".