39409 has 2 divisors, whose sum is σ = 39410. Its totient is φ = 39408.

The previous prime is 39397. The next prime is 39419. The reversal of 39409 is 90493.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34225 + 5184 = 185^2 + 72^2 .

It is a cyclic number.

It is not a de Polignac number, because 39409 - 2¹¹ = 37361 is a prime.

It is an Ulam number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 39409.

It is not a weakly prime, because it can be changed into another prime (39419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19704 + 19705.

It is an arithmetic number, because the mean of its divisors is an integer number (19705).

2³⁹⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

39409 is a deficient number, since it is larger than the sum of its proper divisors (1).

39409 is an equidigital number, since it uses as much as digits as its factorization.

39409 is an odious number, because the sum of its binary digits is odd.

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

The square root of 39409 is about 198.5170017908. The cubic root of 39409 is about 34.0302498952.

It can be divided in two parts, 39 and 409, that multiplied together give a palindrome (15951).

The spelling of 39409 in words is "thirty-nine thousand, four hundred nine".