109855191 has 4 divisors (see below), whose sum is σ = 146473592. Its totient is φ = 73236792.

The previous prime is 109855189. The next prime is 109855201. The reversal of 109855191 is 191558901.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 191558901 = 3 ⋅63852967.

It is not a de Polignac number, because 109855191 - 2¹ = 109855189 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 (109855111) 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, 18309196 + ... + 18309201.

It is an arithmetic number, because the mean of its divisors is an integer number (36618398).

Almost surely, 2^109855191 is an apocalyptic number.

109855191 is a deficient number, since it is larger than the sum of its proper divisors (36618401).

109855191 is an equidigital number, since it uses as much as digits as its factorization.

109855191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36618400.

The product of its (nonzero) digits is 16200, while the sum is 39.

The square root of 109855191 is about 10481.1827099808. The cubic root of 109855191 is about 478.9316386127.

The spelling of 109855191 in words is "one hundred nine million, eight hundred fifty-five thousand, one hundred ninety-one".