191081981982 has 32 divisors (see below), whose sum is σ = 387805638528. Its totient is φ = 62757831456.

The previous prime is 191081981933. The next prime is 191081982017. The reversal of 191081981982 is 289189180191.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 328588 + ... + 700095.

It is an arithmetic number, because the mean of its divisors is an integer number (12118926204).

Almost surely, 2^191081981982 is an apocalyptic number.

191081981982 is an abundant number, since it is smaller than the sum of its proper divisors (196723656546).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

191081981982 is a wasteful number, since it uses less digits than its factorization.

191081981982 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1029144.

The product of its (nonzero) digits is 746496, while the sum is 57.

The spelling of 191081981982 in words is "one hundred ninety-one billion, eighty-one million, nine hundred eighty-one thousand, nine hundred eighty-two".