3781905 has 16 divisors (see below), whose sum is σ = 6407424. Its totient is φ = 1898240.

The previous prime is 3781903. The next prime is 3781909. The reversal of 3781905 is 5091873.

3781905 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 3781905 - 2¹ = 3781903 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

3781905 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (3781901) 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 in 15 ways as a sum of consecutive naturals, for example, 7161 + ... + 7670.

It is an arithmetic number, because the mean of its divisors is an integer number (400464).

Almost surely, 2^3781905 is an apocalyptic number.

It is an amenable number.

3781905 is a deficient number, since it is larger than the sum of its proper divisors (2625519).

3781905 is a wasteful number, since it uses less digits than its factorization.

3781905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14856.

The product of its (nonzero) digits is 7560, while the sum is 33.

The square root of 3781905 is about 1944.7120609489. The cubic root of 3781905 is about 155.8009871826.

The spelling of 3781905 in words is "three million, seven hundred eighty-one thousand, nine hundred five".