39505309 has 2 divisors, whose sum is σ = 39505310. Its totient is φ = 39505308.

The previous prime is 39505303. The next prime is 39505321. The reversal of 39505309 is 90350593.

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., 38402809 + 1102500 = 6197^2 + 1050^2 .

It is a cyclic number.

It is not a de Polignac number, because 39505309 - 2²⁵ = 5950877 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39505303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19752654 + 19752655.

It is an arithmetic number, because the mean of its divisors is an integer number (19752655).

Almost surely, 2^39505309 is an apocalyptic number.

It is an amenable number.

39505309 is a deficient number, since it is larger than the sum of its proper divisors (1).

39505309 is an equidigital number, since it uses as much as digits as its factorization.

39505309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18225, while the sum is 34.

The square root of 39505309 is about 6285.3248921595. The cubic root of 39505309 is about 340.5794875532.

The spelling of 39505309 in words is "thirty-nine million, five hundred five thousand, three hundred nine".