9942839 has 4 divisors (see below), whose sum is σ = 9952440. Its totient is φ = 9933240.

The previous prime is 9942797. The next prime is 9942883. The reversal of 9942839 is 9382499.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 9382499 = 7 ⋅1340357.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9942839 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 9942839.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9942539) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3029 + ... + 5390.

It is an arithmetic number, because the mean of its divisors is an integer number (2488110).

Almost surely, 2^9942839 is an apocalyptic number.

9942839 is a deficient number, since it is larger than the sum of its proper divisors (9601).

9942839 is a wasteful number, since it uses less digits than its factorization.

9942839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9600.

The product of its digits is 139968, while the sum is 44.

The square root of 9942839 is about 3153.2267600032. The cubic root of 9942839 is about 215.0321855547.

The spelling of 9942839 in words is "nine million, nine hundred forty-two thousand, eight hundred thirty-nine".