3831781 has 2 divisors, whose sum is σ = 3831782. Its totient is φ = 3831780.

The previous prime is 3831767. The next prime is 3831811. The reversal of 3831781 is 1871383.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3207681 + 624100 = 1791^2 + 790^2 .

It is an emirp because it is prime and its reverse (1871383) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3831781 - 2¹¹ = 3829733 is a prime.

It is a super-2 number, since 2×3831781² = 29365091263922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3831721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1915890 + 1915891.

It is an arithmetic number, because the mean of its divisors is an integer number (1915891).

Almost surely, 2^3831781 is an apocalyptic number.

It is an amenable number.

3831781 is a deficient number, since it is larger than the sum of its proper divisors (1).

3831781 is an equidigital number, since it uses as much as digits as its factorization.

3831781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 31.

The square root of 3831781 is about 1957.4935504364. The cubic root of 3831781 is about 156.4829025884.

The spelling of 3831781 in words is "three million, eight hundred thirty-one thousand, seven hundred eighty-one".