11931891 has 8 divisors (see below), whose sum is σ = 16058304. Its totient is φ = 7880040.

The previous prime is 11931889. The next prime is 11931901. The reversal of 11931891 is 19813911.

It is a happy number.

11931891 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 not a de Polignac number, because 11931891 - 2¹ = 11931889 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11931811) 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, 18265 + ... + 18906.

It is an arithmetic number, because the mean of its divisors is an integer number (2007288).

Almost surely, 2^11931891 is an apocalyptic number.

11931891 is a deficient number, since it is larger than the sum of its proper divisors (4126413).

11931891 is a wasteful number, since it uses less digits than its factorization.

11931891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37281.

The product of its digits is 1944, while the sum is 33.

The square root of 11931891 is about 3454.2569389089. The cubic root of 11931891 is about 228.5088856598.

The spelling of 11931891 in words is "eleven million, nine hundred thirty-one thousand, eight hundred ninety-one".