3979639 has 2 divisors, whose sum is σ = 3979640. Its totient is φ = 3979638.

The previous prime is 3979637. The next prime is 3979643. The reversal of 3979639 is 9369793.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 3979639 - 2¹ = 3979637 is a prime.

Together with 3979637, it forms a pair of twin primes.

3979639 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3979637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1989819 + 1989820.

It is an arithmetic number, because the mean of its divisors is an integer number (1989820).

Almost surely, 2^3979639 is an apocalyptic number.

3979639 is a deficient number, since it is larger than the sum of its proper divisors (1).

3979639 is an equidigital number, since it uses as much as digits as its factorization.

3979639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 275562, while the sum is 46.

The square root of 3979639 is about 1994.9032557996. The cubic root of 3979639 is about 158.4703046200.

The spelling of 3979639 in words is "three million, nine hundred seventy-nine thousand, six hundred thirty-nine".