198771839 has 4 divisors (see below), whose sum is σ = 227167824. Its totient is φ = 170375856.

The previous prime is 198771827. The next prime is 198771841. The reversal of 198771839 is 938177891.

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

It is not a de Polignac number, because 198771839 - 2⁴ = 198771823 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198771809) 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, 14197982 + ... + 14197995.

It is an arithmetic number, because the mean of its divisors is an integer number (56791956).

Almost surely, 2^198771839 is an apocalyptic number.

198771839 is a deficient number, since it is larger than the sum of its proper divisors (28395985).

198771839 is an equidigital number, since it uses as much as digits as its factorization.

198771839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28395984.

The product of its digits is 762048, while the sum is 53.

The square root of 198771839 is about 14098.6467081064. The cubic root of 198771839 is about 583.6040341056.

The spelling of 198771839 in words is "one hundred ninety-eight million, seven hundred seventy-one thousand, eight hundred thirty-nine".