21312332244 has 108 divisors (see below), whose sum is σ = 62867747124. Its totient is φ = 6069869568.

The previous prime is 21312332233. The next prime is 21312332309. The reversal of 21312332244 is 44223321312.

21312332244 is a `hidden beast` number, since 21 + 312 + 3 + 322 + 4 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 5804611344 + 15507720900 = 76188^2 + 124530^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 540132 + ... + 578244.

Almost surely, 2^21312332244 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 21312332244, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31433873562).

21312332244 is an abundant number, since it is smaller than the sum of its proper divisors (41555414880).

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

21312332244 is a wasteful number, since it uses less digits than its factorization.

21312332244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38454 (or 38442 counting only the distinct ones).

The product of its digits is 6912, while the sum is 27.

Adding to 21312332244 its reverse (44223321312), we get a palindrome (65535653556).

The spelling of 21312332244 in words is "twenty-one billion, three hundred twelve million, three hundred thirty-two thousand, two hundred forty-four".