3940009 has 2 divisors, whose sum is σ = 3940010. Its totient is φ = 3940008.

The previous prime is 3939997. The next prime is 3940021. The reversal of 3940009 is 9000493.

It is a balanced prime because it is at equal distance from previous prime (3939997) and next prime (3940021).

It can be written as a sum of positive squares in only one way, i.e., 2624400 + 1315609 = 1620^2 + 1147^2 .

It is a cyclic number.

It is not a de Polignac number, because 3940009 - 2⁹ = 3939497 is a prime.

It is not a weakly prime, because it can be changed into another prime (3940099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1970004 + 1970005.

It is an arithmetic number, because the mean of its divisors is an integer number (1970005).

Almost surely, 2^3940009 is an apocalyptic number.

It is an amenable number.

3940009 is a deficient number, since it is larger than the sum of its proper divisors (1).

3940009 is an equidigital number, since it uses as much as digits as its factorization.

3940009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 3940009 is about 1984.9455911939. The cubic root of 3940009 is about 157.9425230236.

The spelling of 3940009 in words is "three million, nine hundred forty thousand, nine".