9909942 has 16 divisors (see below), whose sum is σ = 22651392. Its totient is φ = 2831400.

The previous prime is 9909917. The next prime is 9909943. The reversal of 9909942 is 2499099.

It is a Harshad number since it is a multiple of its sum of digits (42), and also a Moran number because the ratio is a prime number: 235951 = 9909942 / (9 + 9 + 0 + 9 + 9 + 4 + 2).

It is a junction number, because it is equal to n+sod(n) for n = 9909894 and 9909903.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9909943) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 117934 + ... + 118017.

It is an arithmetic number, because the mean of its divisors is an integer number (1415712).

Almost surely, 2^9909942 is an apocalyptic number.

9909942 is an abundant number, since it is smaller than the sum of its proper divisors (12741450).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9909942 is a wasteful number, since it uses less digits than its factorization.

9909942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235963.

The product of its (nonzero) digits is 52488, while the sum is 42.

The square root of 9909942 is about 3148.0060355724. The cubic root of 9909942 is about 214.7947708085.

The spelling of 9909942 in words is "nine million, nine hundred nine thousand, nine hundred forty-two".