42399939 has 4 divisors (see below), whose sum is σ = 56533256. Its totient is φ = 28266624.

The previous prime is 42399913. The next prime is 42399953. The reversal of 42399939 is 93999324.

It is a happy number.

42399939 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 42399939 - 2¹⁹ = 41875651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42399979) 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 in 3 ways as a sum of consecutive naturals, for example, 7066654 + ... + 7066659.

It is an arithmetic number, because the mean of its divisors is an integer number (14133314).

Almost surely, 2^42399939 is an apocalyptic number.

42399939 is a deficient number, since it is larger than the sum of its proper divisors (14133317).

42399939 is a wasteful number, since it uses less digits than its factorization.

42399939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14133316.

The product of its digits is 472392, while the sum is 48.

The square root of 42399939 is about 6511.5235544379. The cubic root of 42399939 is about 348.7025130292.

The spelling of 42399939 in words is "forty-two million, three hundred ninety-nine thousand, nine hundred thirty-nine".