21231132312 has 128 divisors (see below), whose sum is σ = 60590980800. Its totient is φ = 6141493248.

The previous prime is 21231132283. The next prime is 21231132313. The reversal of 21231132312 is 21323113212.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231132313) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6516988 + ... + 6520244.

Almost surely, 2^21231132312 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 21231132312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30295490400).

21231132312 is an abundant number, since it is smaller than the sum of its proper divisors (39359848488).

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

21231132312 is a wasteful number, since it uses less digits than its factorization.

21231132312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4525 (or 4521 counting only the distinct ones).

The product of its digits is 432, while the sum is 21.

Adding to 21231132312 its reverse (21323113212), we get a palindrome (42554245524).

The spelling of 21231132312 in words is "twenty-one billion, two hundred thirty-one million, one hundred thirty-two thousand, three hundred twelve".