3947409 has 6 divisors (see below), whose sum is σ = 5701826. Its totient is φ = 2631600.

The previous prime is 3947407. The next prime is 3947413. The reversal of 3947409 is 9047493.

It can be written as a sum of positive squares in only one way, i.e., 2471184 + 1476225 = 1572^2 + 1215^2 .

It is not a de Polignac number, because 3947409 - 2¹ = 3947407 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3947401) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 219292 + ... + 219309.

Almost surely, 2^3947409 is an apocalyptic number.

It is an amenable number.

3947409 is a deficient number, since it is larger than the sum of its proper divisors (1754417).

3947409 is a wasteful number, since it uses less digits than its factorization.

3947409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438607 (or 438604 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 36.

The square root of 3947409 is about 1986.8087477158. The cubic root of 3947409 is about 158.0413420630.

It can be divided in two parts, 3947 and 409, that added together give a square (4356 = 66²).

The spelling of 3947409 in words is "three million, nine hundred forty-seven thousand, four hundred nine".