11641891 has 4 divisors (see below), whose sum is σ = 11657800. Its totient is φ = 11625984.

The previous prime is 11641879. The next prime is 11641897. The reversal of 11641891 is 19814611.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19814611 = 31 ⋅639181.

It is a cyclic number.

It is not a de Polignac number, because 11641891 - 2⁵ = 11641859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11641897) 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, 6801 + ... + 8338.

It is an arithmetic number, because the mean of its divisors is an integer number (2914450).

Almost surely, 2^11641891 is an apocalyptic number.

11641891 is a deficient number, since it is larger than the sum of its proper divisors (15909).

11641891 is an equidigital number, since it uses as much as digits as its factorization.

11641891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15908.

The product of its digits is 1728, while the sum is 31.

The square root of 11641891 is about 3412.0215415498. The cubic root of 11641891 is about 226.6424082555.

The spelling of 11641891 in words is "eleven million, six hundred forty-one thousand, eight hundred ninety-one".