21132012 has 24 divisors (see below), whose sum is σ = 53790912. Its totient is φ = 6403600.

The previous prime is 21132011. The next prime is 21132061. The reversal of 21132012 is 21023112.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (21132011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79914 + ... + 80177.

It is an arithmetic number, because the mean of its divisors is an integer number (2241288).

Almost surely, 2^21132012 is an apocalyptic number.

21132012 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21132012 is an abundant number, since it is smaller than the sum of its proper divisors (32658900).

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

21132012 is a wasteful number, since it uses less digits than its factorization.

21132012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160109 (or 160107 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 21132012 is about 4596.9568194622. The cubic root of 21132012 is about 276.4693233115.

Adding to 21132012 its reverse (21023112), we get a palindrome (42155124).

Subtracting from 21132012 its reverse (21023112), we obtain a square (108900 = 330²).

It can be divided in two parts, 211 and 32012, that added together give a palindrome (32223).

The spelling of 21132012 in words is "twenty-one million, one hundred thirty-two thousand, twelve".