195998839 has 4 divisors (see below), whose sum is σ = 197733456. Its totient is φ = 194264224.

The previous prime is 195998809. The next prime is 195998897. The reversal of 195998839 is 938899591.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 938899591 = 7 ⋅134128513.

It is a cyclic number.

It is not a de Polignac number, because 195998839 - 2⁵ = 195998807 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (195998809) 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, 867139 + ... + 867364.

It is an arithmetic number, because the mean of its divisors is an integer number (49433364).

Almost surely, 2^195998839 is an apocalyptic number.

195998839 is a deficient number, since it is larger than the sum of its proper divisors (1734617).

195998839 is a wasteful number, since it uses less digits than its factorization.

195998839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1734616.

The product of its digits is 6298560, while the sum is 61.

The square root of 195998839 is about 13999.9585356529. The cubic root of 195998839 is about 580.8774264153.

The spelling of 195998839 in words is "one hundred ninety-five million, nine hundred ninety-eight thousand, eight hundred thirty-nine".