3928681 has 2 divisors, whose sum is σ = 3928682. Its totient is φ = 3928680.

The previous prime is 3928669. The next prime is 3928703. The reversal of 3928681 is 1868293.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3920400 + 8281 = 1980^2 + 91^2 .

It is a cyclic number.

It is not a de Polignac number, because 3928681 - 2⁷ = 3928553 is a prime.

It is a super-2 number, since 2×3928681² = 30869068799522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 3928681.

It is not a weakly prime, because it can be changed into another prime (3928621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1964340 + 1964341.

It is an arithmetic number, because the mean of its divisors is an integer number (1964341).

Almost surely, 2^3928681 is an apocalyptic number.

It is an amenable number.

3928681 is a deficient number, since it is larger than the sum of its proper divisors (1).

3928681 is an equidigital number, since it uses as much as digits as its factorization.

3928681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 37.

The square root of 3928681 is about 1982.0900584989. The cubic root of 3928681 is about 157.7910098045.

The spelling of 3928681 in words is "three million, nine hundred twenty-eight thousand, six hundred eighty-one".