8105991 has 8 divisors (see below), whose sum is σ = 11443824. Its totient is φ = 5086080.

The previous prime is 8105983. The next prime is 8106001. The reversal of 8105991 is 1995018.

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

It is not a de Polignac number, because 8105991 - 2³ = 8105983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8105921) 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, 79420 + ... + 79521.

It is an arithmetic number, because the mean of its divisors is an integer number (1430478).

Almost surely, 2^8105991 is an apocalyptic number.

8105991 is a deficient number, since it is larger than the sum of its proper divisors (3337833).

8105991 is a wasteful number, since it uses less digits than its factorization.

8105991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158961.

The product of its (nonzero) digits is 3240, while the sum is 33.

The square root of 8105991 is about 2847.1022110209. The cubic root of 8105991 is about 200.8793860670.

The spelling of 8105991 in words is "eight million, one hundred five thousand, nine hundred ninety-one".