3909905 has 8 divisors (see below), whose sum is σ = 4702632. Its totient is φ = 3120768.

The previous prime is 3909889. The next prime is 3909907. The reversal of 3909905 is 5099093.

3909905 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 1547536 + 2362369 = 1244^2 + 1537^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3909905 - 2⁴ = 3909889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3909907) 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 7 ways as a sum of consecutive naturals, for example, 3269 + ... + 4301.

It is an arithmetic number, because the mean of its divisors is an integer number (587829).

Almost surely, 2^3909905 is an apocalyptic number.

It is an amenable number.

3909905 is a deficient number, since it is larger than the sum of its proper divisors (792727).

3909905 is a wasteful number, since it uses less digits than its factorization.

3909905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1795.

The product of its (nonzero) digits is 10935, while the sum is 35.

The square root of 3909905 is about 1977.3479714001. The cubic root of 3909905 is about 157.5392360466.

The spelling of 3909905 in words is "three million, nine hundred nine thousand, nine hundred five".