4009639 has 2 divisors, whose sum is σ = 4009640. Its totient is φ = 4009638.

The previous prime is 4009631. The next prime is 4009667. The reversal of 4009639 is 9369004.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 4009639 - 2³ = 4009631 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 4009639.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4009631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2004819 + 2004820.

It is an arithmetic number, because the mean of its divisors is an integer number (2004820).

Almost surely, 2^4009639 is an apocalyptic number.

4009639 is a deficient number, since it is larger than the sum of its proper divisors (1).

4009639 is an equidigital number, since it uses as much as digits as its factorization.

4009639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5832, while the sum is 31.

The square root of 4009639 is about 2002.4083000228. The cubic root of 4009639 is about 158.8675109024.

The spelling of 4009639 in words is "four million, nine thousand, six hundred thirty-nine".