21231320112 has 30 divisors (see below), whose sum is σ = 59418208772. Its totient is φ = 7077106656.

The previous prime is 21231320107. The next prime is 21231320153. The reversal of 21231320112 is 21102313212.

21231320112 is a `hidden beast` number, since 2 + 1 + 231 + 320 + 112 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 73719718 + ... + 73720005.

Almost surely, 2^21231320112 is an apocalyptic number.

It is an amenable number.

21231320112 is an abundant number, since it is smaller than the sum of its proper divisors (38186888660).

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

21231320112 is a wasteful number, since it uses less digits than its factorization.

21231320112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147439737 (or 147439728 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21231320112 its reverse (21102313212), we get a palindrome (42333633324).

The spelling of 21231320112 in words is "twenty-one billion, two hundred thirty-one million, three hundred twenty thousand, one hundred twelve".