3956681 has 2 divisors, whose sum is σ = 3956682. Its totient is φ = 3956680.

The previous prime is 3956677. The next prime is 3956737. The reversal of 3956681 is 1866593.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2371600 + 1585081 = 1540^2 + 1259^2 .

It is an emirp because it is prime and its reverse (1866593) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3956681 - 2² = 3956677 is a prime.

It is a super-2 number, since 2×3956681² = 31310649071522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is an Ulam number.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (3956651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1978340 + 1978341.

It is an arithmetic number, because the mean of its divisors is an integer number (1978341).

Almost surely, 2^3956681 is an apocalyptic number.

It is an amenable number.

3956681 is a deficient number, since it is larger than the sum of its proper divisors (1).

3956681 is an equidigital number, since it uses as much as digits as its factorization.

3956681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 38880, while the sum is 38.

The square root of 3956681 is about 1989.1407692770. The cubic root of 3956681 is about 158.1649854875.

The spelling of 3956681 in words is "three million, nine hundred fifty-six thousand, six hundred eighty-one".