191081 has 8 divisors (see below), whose sum is σ = 216000. Its totient is φ = 167440.

The previous prime is 191071. The next prime is 191089. The reversal of 191081 is 180191.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-191081 is a prime.

It is a super-2 number, since 2×191081² = 73023897122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (191089) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20 + ... + 618.

It is an arithmetic number, because the mean of its divisors is an integer number (27000).

2¹⁹¹⁰⁸¹ is an apocalyptic number.

191081 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

191081 is a deficient number, since it is larger than the sum of its proper divisors (24919).

191081 is a wasteful number, since it uses less digits than its factorization.

191081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 639.

The product of its (nonzero) digits is 72, while the sum is 20.

The square root of 191081 is about 437.1281276697. The cubic root of 191081 is about 57.5977920000.

It can be divided in two parts, 1910 and 81, that added together give a palindrome (1991).

The spelling of 191081 in words is "one hundred ninety-one thousand, eighty-one".