3981181 has 2 divisors, whose sum is σ = 3981182. Its totient is φ = 3981180.

The previous prime is 3981169. The next prime is 3981191. The reversal of 3981181 is 1811893.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3980025 + 1156 = 1995^2 + 34^2 .

It is an emirp because it is prime and its reverse (1811893) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3981181 - 2¹¹ = 3979133 is a prime.

It is a super-2 number, since 2×3981181² = 31699604309522, which contains 22 as substring.

3981181 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3981101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1990590 + 1990591.

It is an arithmetic number, because the mean of its divisors is an integer number (1990591).

Almost surely, 2^3981181 is an apocalyptic number.

It is an amenable number.

3981181 is a deficient number, since it is larger than the sum of its proper divisors (1).

3981181 is an equidigital number, since it uses as much as digits as its factorization.

3981181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1728, while the sum is 31.

The square root of 3981181 is about 1995.2897032762. The cubic root of 3981181 is about 158.4907695965.

The spelling of 3981181 in words is "three million, nine hundred eighty-one thousand, one hundred eighty-one".