39995309 has 2 divisors, whose sum is σ = 39995310. Its totient is φ = 39995308.

The previous prime is 39995303. The next prime is 39995311. The reversal of 39995309 is 90359993.

It is a happy number.

39995309 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38502025 + 1493284 = 6205^2 + 1222^2 .

It is a cyclic number.

It is not a de Polignac number, because 39995309 - 2¹² = 39991213 is a prime.

Together with 39995311, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39995303) 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, 19997654 + 19997655.

It is an arithmetic number, because the mean of its divisors is an integer number (19997655).

Almost surely, 2^39995309 is an apocalyptic number.

It is an amenable number.

39995309 is a deficient number, since it is larger than the sum of its proper divisors (1).

39995309 is an equidigital number, since it uses as much as digits as its factorization.

39995309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 295245, while the sum is 47.

The square root of 39995309 is about 6324.1844533505. The cubic root of 39995309 is about 341.9818196507.

It can be divided in two parts, 39995 and 309, that added together give a palindrome (40304).

The spelling of 39995309 in words is "thirty-nine million, nine hundred ninety-five thousand, three hundred nine".