3781643 has 2 divisors, whose sum is σ = 3781644. Its totient is φ = 3781642.

The previous prime is 3781639. The next prime is 3781649. The reversal of 3781643 is 3461873.

3781643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 3781643 - 2² = 3781639 is a prime.

It is not a weakly prime, because it can be changed into another prime (3781649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1890821 + 1890822.

It is an arithmetic number, because the mean of its divisors is an integer number (1890822).

Almost surely, 2^3781643 is an apocalyptic number.

3781643 is a deficient number, since it is larger than the sum of its proper divisors (1).

3781643 is an equidigital number, since it uses as much as digits as its factorization.

3781643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 32.

The square root of 3781643 is about 1944.6446976247. The cubic root of 3781643 is about 155.7973892779.

The spelling of 3781643 in words is "three million, seven hundred eighty-one thousand, six hundred forty-three".