12131881 has 4 divisors (see below), whose sum is σ = 12523264. Its totient is φ = 11740500.

The previous prime is 12131849. The next prime is 12131909. The reversal of 12131881 is 18813121.

12131881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 12131881 - 2⁵ = 12131849 is a prime.

It is a super-2 number, since 2×12131881² = 294365073196322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12131681) 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, 195645 + ... + 195706.

It is an arithmetic number, because the mean of its divisors is an integer number (3130816).

Almost surely, 2^12131881 is an apocalyptic number.

It is an amenable number.

12131881 is a deficient number, since it is larger than the sum of its proper divisors (391383).

12131881 is an equidigital number, since it uses as much as digits as its factorization.

12131881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391382.

The product of its digits is 384, while the sum is 25.

The square root of 12131881 is about 3483.0849831722. The cubic root of 12131881 is about 229.7784949993.

The spelling of 12131881 in words is "twelve million, one hundred thirty-one thousand, eight hundred eighty-one".