191981449775 has 6 divisors (see below), whose sum is σ = 238056997752. Its totient is φ = 153585159800.

The previous prime is 191981449757. The next prime is 191981449859. The reversal of 191981449775 is 577944189191.

It is not a de Polignac number, because 191981449775 - 2⁸ = 191981449519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3839628971 + ... + 3839629020.

It is an arithmetic number, because the mean of its divisors is an integer number (39676166292).

Almost surely, 2^191981449775 is an apocalyptic number.

191981449775 is a deficient number, since it is larger than the sum of its proper divisors (46075547977).

191981449775 is an equidigital number, since it uses as much as digits as its factorization.

191981449775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7679258001 (or 7679257996 counting only the distinct ones).

The product of its digits is 22861440, while the sum is 65.

The spelling of 191981449775 in words is "one hundred ninety-one billion, nine hundred eighty-one million, four hundred forty-nine thousand, seven hundred seventy-five".