8191331 has 4 divisors (see below), whose sum is σ = 8673192. Its totient is φ = 7709472.

The previous prime is 8191321. The next prime is 8191333. The reversal of 8191331 is 1331918.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8191331 is a prime.

It is a super-2 number, since 2×8191331² = 134195807103122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 8191331.

It is not an unprimeable number, because it can be changed into a prime (8191333) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 240905 + ... + 240938.

It is an arithmetic number, because the mean of its divisors is an integer number (2168298).

Almost surely, 2^8191331 is an apocalyptic number.

8191331 is a deficient number, since it is larger than the sum of its proper divisors (481861).

8191331 is a wasteful number, since it uses less digits than its factorization.

8191331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 481860.

The product of its digits is 648, while the sum is 26.

The square root of 8191331 is about 2862.0501393232. The cubic root of 8191331 is about 201.5818802870.

The spelling of 8191331 in words is "eight million, one hundred ninety-one thousand, three hundred thirty-one".