18486191 has 4 divisors (see below), whose sum is σ = 19573632. Its totient is φ = 17398752.

The previous prime is 18486161. The next prime is 18486197. The reversal of 18486191 is 19168481.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19168481 = 79 ⋅242639.

It is not a de Polignac number, because 18486191 - 2¹⁸ = 18224047 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18486197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 543695 + ... + 543728.

It is an arithmetic number, because the mean of its divisors is an integer number (4893408).

Almost surely, 2^18486191 is an apocalyptic number.

18486191 is a deficient number, since it is larger than the sum of its proper divisors (1087441).

18486191 is a wasteful number, since it uses less digits than its factorization.

18486191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1087440.

The product of its digits is 13824, while the sum is 38.

The square root of 18486191 is about 4299.5570702108. The cubic root of 18486191 is about 264.4128021141.

The spelling of 18486191 in words is "eighteen million, four hundred eighty-six thousand, one hundred ninety-one".