21112031121 has 8 divisors (see below), whose sum is σ = 28545845184. Its totient is φ = 13876452240.

The previous prime is 21112031113. The next prime is 21112031141. The reversal of 21112031121 is 12113021112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21112031121 - 2³ = 21112031113 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21112031121.

It is not an unprimeable number, because it can be changed into a prime (21112031141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49558546 + ... + 49558971.

It is an arithmetic number, because the mean of its divisors is an integer number (3568230648).

Almost surely, 2^21112031121 is an apocalyptic number.

It is an amenable number.

21112031121 is a deficient number, since it is larger than the sum of its proper divisors (7433814063).

21112031121 is an equidigital number, since it uses as much as digits as its factorization.

21112031121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99117591.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 21112031121 its reverse (12113021112), we get a palindrome (33225052233).

The spelling of 21112031121 in words is "twenty-one billion, one hundred twelve million, thirty-one thousand, one hundred twenty-one".