11955891 has 4 divisors (see below), whose sum is σ = 15941192. Its totient is φ = 7970592.

The previous prime is 11955877. The next prime is 11955941. The reversal of 11955891 is 19855911.

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

It is not a de Polignac number, because 11955891 - 2¹⁰ = 11954867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11955821) 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, 1992646 + ... + 1992651.

It is an arithmetic number, because the mean of its divisors is an integer number (3985298).

Almost surely, 2^11955891 is an apocalyptic number.

11955891 is a deficient number, since it is larger than the sum of its proper divisors (3985301).

11955891 is an equidigital number, since it uses as much as digits as its factorization.

11955891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3985300.

The product of its digits is 16200, while the sum is 39.

The square root of 11955891 is about 3457.7291681102. The cubic root of 11955891 is about 228.6619918843.

The spelling of 11955891 in words is "eleven million, nine hundred fifty-five thousand, eight hundred ninety-one".