8105981 has 4 divisors (see below), whose sum is σ = 8729532. Its totient is φ = 7482432.

The previous prime is 8105941. The next prime is 8105983. The reversal of 8105981 is 1895018.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1895018 = 2 ⋅947509.

It can be written as a sum of positive squares in 2 ways, for example, as 3115225 + 4990756 = 1765^2 + 2234^2 .

It is a cyclic number.

It is not a de Polignac number, because 8105981 - 2¹⁴ = 8089597 is a prime.

It is a super-2 number, since 2×8105981² = 131413855944722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8105983) 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, 311756 + ... + 311781.

It is an arithmetic number, because the mean of its divisors is an integer number (2182383).

Almost surely, 2^8105981 is an apocalyptic number.

It is an amenable number.

8105981 is a deficient number, since it is larger than the sum of its proper divisors (623551).

8105981 is a wasteful number, since it uses less digits than its factorization.

8105981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 623550.

The product of its (nonzero) digits is 2880, while the sum is 32.

The square root of 8105981 is about 2847.1004548488. The cubic root of 8105981 is about 200.8793034617.

The spelling of 8105981 in words is "eight million, one hundred five thousand, nine hundred eighty-one".