18441891 has 16 divisors (see below), whose sum is σ = 29423520. Its totient is φ = 11348640.

The previous prime is 18441887. The next prime is 18441911. The reversal of 18441891 is 19814481.

It is not a de Polignac number, because 18441891 - 2² = 18441887 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18441811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25920 + ... + 26621.

It is an arithmetic number, because the mean of its divisors is an integer number (1838970).

Almost surely, 2^18441891 is an apocalyptic number.

18441891 is a deficient number, since it is larger than the sum of its proper divisors (10981629).

18441891 is a wasteful number, since it uses less digits than its factorization.

18441891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52563 (or 52557 counting only the distinct ones).

The product of its digits is 9216, while the sum is 36.

The square root of 18441891 is about 4294.4022866983. The cubic root of 18441891 is about 264.2014216972.

The spelling of 18441891 in words is "eighteen million, four hundred forty-one thousand, eight hundred ninety-one".