191011982993 has 4 divisors (see below), whose sum is σ = 205705212468. Its totient is φ = 176318753520.

The previous prime is 191011982981. The next prime is 191011983007. The reversal of 191011982993 is 399289110191.

191011982993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 399289110191 = 1877 ⋅212727283.

It can be written as a sum of positive squares in 2 ways, for example, as 20924201104 + 170087781889 = 144652^2 + 412417^2 .

It is not a de Polignac number, because 191011982993 - 2¹⁰ = 191011981969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (191011982093) 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 3 ways as a sum of consecutive naturals, for example, 7346614718 + ... + 7346614743.

It is an arithmetic number, because the mean of its divisors is an integer number (51426303117).

Almost surely, 2^191011982993 is an apocalyptic number.

191011982993 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

191011982993 is a deficient number, since it is larger than the sum of its proper divisors (14693229475).

191011982993 is a wasteful number, since it uses less digits than its factorization.

191011982993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14693229474.

The product of its (nonzero) digits is 314928, while the sum is 53.

The spelling of 191011982993 in words is "one hundred ninety-one billion, eleven million, nine hundred eighty-two thousand, nine hundred ninety-three".