39999943 has 2 divisors, whose sum is σ = 39999944. Its totient is φ = 39999942.

The previous prime is 39999931. The next prime is 39999979. The reversal of 39999943 is 34999993.

39999943 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 39999943 - 2⁹ = 39999431 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39999913) 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, 19999971 + 19999972.

It is an arithmetic number, because the mean of its divisors is an integer number (19999972).

Almost surely, 2^39999943 is an apocalyptic number.

39999943 is a deficient number, since it is larger than the sum of its proper divisors (1).

39999943 is an equidigital number, since it uses as much as digits as its factorization.

39999943 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2125764, while the sum is 55.

The square root of 39999943 is about 6324.5508140895. The cubic root of 39999943 is about 341.9950268875.

The spelling of 39999943 in words is "thirty-nine million, nine hundred ninety-nine thousand, nine hundred forty-three".