11918791 has 4 divisors (see below), whose sum is σ = 12052800. Its totient is φ = 11784784.

The previous prime is 11918789. The next prime is 11918813. The reversal of 11918791 is 19781911.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19781911 = 859 ⋅23029.

It is a cyclic number.

It is not a de Polignac number, because 11918791 - 2¹ = 11918789 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11918791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11918701) 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, 66871 + ... + 67048.

It is an arithmetic number, because the mean of its divisors is an integer number (3013200).

Almost surely, 2^11918791 is an apocalyptic number.

11918791 is a deficient number, since it is larger than the sum of its proper divisors (134009).

11918791 is an equidigital number, since it uses as much as digits as its factorization.

11918791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134008.

The product of its digits is 4536, while the sum is 37.

The square root of 11918791 is about 3452.3602071626. The cubic root of 11918791 is about 228.4252285491.

The spelling of 11918791 in words is "eleven million, nine hundred eighteen thousand, seven hundred ninety-one".