21112131331 has 4 divisors (see below), whose sum is σ = 21116407392. Its totient is φ = 21107855272.

The previous prime is 21112131311. The next prime is 21112131361. The reversal of 21112131331 is 13313121112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21112131331 - 2¹⁵ = 21112098563 is a prime.

It is a super-2 number, since 2×21112131331² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21112131299 and 21112131308.

It is not an unprimeable number, because it can be changed into a prime (21112131311) 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, 2130616 + ... + 2140501.

It is an arithmetic number, because the mean of its divisors is an integer number (5279101848).

Almost surely, 2^21112131331 is an apocalyptic number.

21112131331 is a deficient number, since it is larger than the sum of its proper divisors (4276061).

21112131331 is an equidigital number, since it uses as much as digits as its factorization.

21112131331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4276060.

The product of its digits is 108, while the sum is 19.

Adding to 21112131331 its reverse (13313121112), we get a palindrome (34425252443).

The spelling of 21112131331 in words is "twenty-one billion, one hundred twelve million, one hundred thirty-one thousand, three hundred thirty-one".