21132412 has 24 divisors (see below), whose sum is σ = 42363104. Its totient is φ = 9035712.

The previous prime is 21132383. The next prime is 21132481. The reversal of 21132412 is 21423112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20698 + ... + 21694.

Almost surely, 2^21132412 is an apocalyptic number.

It is an amenable number.

21132412 is an abundant number, since it is smaller than the sum of its proper divisors (21230692).

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

21132412 is a wasteful number, since it uses less digits than its factorization.

21132412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1765 (or 1763 counting only the distinct ones).

The product of its digits is 96, while the sum is 16.

The square root of 21132412 is about 4597.0003262997. Note that the first 3 decimals coincide. The cubic root of 21132412 is about 276.4710676955.

Adding to 21132412 its reverse (21423112), we get a palindrome (42555524).

It can be divided in two parts, 211 and 32412, that added together give a palindrome (32623).

The spelling of 21132412 in words is "twenty-one million, one hundred thirty-two thousand, four hundred twelve".