12871991 has 8 divisors (see below), whose sum is σ = 14385168. Its totient is φ = 11416000.

The previous prime is 12871933. The next prime is 12872003. The reversal of 12871991 is 19917821.

12871991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 12871991 - 2¹⁰ = 12870967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12871291) 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, 13820 + ... + 14721.

It is an arithmetic number, because the mean of its divisors is an integer number (1798146).

Almost surely, 2^12871991 is an apocalyptic number.

12871991 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

12871991 is a deficient number, since it is larger than the sum of its proper divisors (1513177).

12871991 is a wasteful number, since it uses less digits than its factorization.

12871991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28593.

The product of its digits is 9072, while the sum is 38.

The square root of 12871991 is about 3587.7557051728. The cubic root of 12871991 is about 234.3591472774.

The spelling of 12871991 in words is "twelve million, eight hundred seventy-one thousand, nine hundred ninety-one".