3905643 has 18 divisors (see below), whose sum is σ = 6095124. Its totient is φ = 2218104.

The previous prime is 3905641. The next prime is 3905651. The reversal of 3905643 is 3465093.

It is a happy number.

It is not a de Polignac number, because 3905643 - 2¹ = 3905641 is a prime.

3905643 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 3905643.

It is not an unprimeable number, because it can be changed into a prime (3905641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 23880 + ... + 24042.

It is an arithmetic number, because the mean of its divisors is an integer number (338618).

Almost surely, 2^3905643 is an apocalyptic number.

3905643 is a deficient number, since it is larger than the sum of its proper divisors (2189481).

3905643 is an equidigital number, since it uses as much as digits as its factorization.

3905643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343 (or 173 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 30.

The square root of 3905643 is about 1976.2699714361. The cubic root of 3905643 is about 157.4819732455.

The spelling of 3905643 in words is "three million, nine hundred five thousand, six hundred forty-three".