8191181 has 2 divisors, whose sum is σ = 8191182. Its totient is φ = 8191180.

The previous prime is 8191133. The next prime is 8191189. The reversal of 8191181 is 1811918.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6325225 + 1865956 = 2515^2 + 1366^2 .

It is a cyclic number.

It is not a de Polignac number, because 8191181 - 2¹⁰ = 8190157 is a prime.

It is a super-2 number, since 2×8191181² = 134190892349522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8191189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4095590 + 4095591.

It is an arithmetic number, because the mean of its divisors is an integer number (4095591).

Almost surely, 2^8191181 is an apocalyptic number.

It is an amenable number.

8191181 is a deficient number, since it is larger than the sum of its proper divisors (1).

8191181 is an equidigital number, since it uses as much as digits as its factorization.

8191181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 29.

The square root of 8191181 is about 2862.0239342116. The cubic root of 8191181 is about 201.5806498209.

The spelling of 8191181 in words is "eight million, one hundred ninety-one thousand, one hundred eighty-one".