99842 has 4 divisors (see below), whose sum is σ = 149766. Its totient is φ = 49920.

The previous prime is 99839. The next prime is 99859. The reversal of 99842 is 24899.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24899 = 7 ⋅3557.

It can be written as a sum of positive squares in only one way, i.e., 67081 + 32761 = 259^2 + 181^2 .

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 99799 and 99808.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 99842.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 24959 + ... + 24962.

2⁹⁹⁸⁴² is an apocalyptic number.

99842 is a deficient number, since it is larger than the sum of its proper divisors (49924).

99842 is a wasteful number, since it uses less digits than its factorization.

99842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49923.

The product of its digits is 5184, while the sum is 32.

The square root of 99842 is about 315.9778473248. The cubic root of 99842 is about 46.3914297489.

The spelling of 99842 in words is "ninety-nine thousand, eight hundred forty-two".