21132312 has 16 divisors (see below), whose sum is σ = 52830840. Its totient is φ = 7044096.

The previous prime is 21132311. The next prime is 21132317. The reversal of 21132312 is 21323112.

It is a super-2 number, since 2×21132312² = 893149220930688, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 21132291 and 21132300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21132311) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 440233 + ... + 440280.

Almost surely, 2^21132312 is an apocalyptic number.

It is an amenable number.

21132312 is an abundant number, since it is smaller than the sum of its proper divisors (31698528).

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

21132312 is a wasteful number, since it uses less digits than its factorization.

21132312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 880522 (or 880518 counting only the distinct ones).

The product of its digits is 72, while the sum is 15.

The square root of 21132312 is about 4596.9894496290. The cubic root of 21132312 is about 276.4706316016.

Adding to 21132312 its reverse (21323112), we get a palindrome (42455424).

It can be divided in two parts, 211 and 32312, that added together give a palindrome (32523).

The spelling of 21132312 in words is "twenty-one million, one hundred thirty-two thousand, three hundred twelve".