3939997 has 2 divisors, whose sum is σ = 3939998. Its totient is φ = 3939996.

The previous prime is 3939989. The next prime is 3940009. The reversal of 3939997 is 7999393.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3437316 + 502681 = 1854^2 + 709^2 .

It is an emirp because it is prime and its reverse (7999393) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3939997 - 2³ = 3939989 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 3939997.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3939907) 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 as a sum of consecutive naturals, namely, 1969998 + 1969999.

It is an arithmetic number, because the mean of its divisors is an integer number (1969999).

Almost surely, 2^3939997 is an apocalyptic number.

It is an amenable number.

3939997 is a deficient number, since it is larger than the sum of its proper divisors (1).

3939997 is an equidigital number, since it uses as much as digits as its factorization.

3939997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 413343, while the sum is 49.

The square root of 3939997 is about 1984.9425684387. The cubic root of 3939997 is about 157.9423626760.

The spelling of 3939997 in words is "three million, nine hundred thirty-nine thousand, nine hundred ninety-seven".