18211189791 has 16 divisors (see below), whose sum is σ = 24389624448. Its totient is φ = 12086820000.

The previous prime is 18211189771. The next prime is 18211189793. The reversal of 18211189791 is 19798111281.

It is not a de Polignac number, because 18211189791 - 2⁷ = 18211189663 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18211189791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18211189793) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2192356 + ... + 2200646.

It is an arithmetic number, because the mean of its divisors is an integer number (1524351528).

Almost surely, 2^18211189791 is an apocalyptic number.

18211189791 is a deficient number, since it is larger than the sum of its proper divisors (6178434657).

18211189791 is a wasteful number, since it uses less digits than its factorization.

18211189791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11462.

The product of its digits is 72576, while the sum is 48.

The spelling of 18211189791 in words is "eighteen billion, two hundred eleven million, one hundred eighty-nine thousand, seven hundred ninety-one".