198781768 has 8 divisors (see below), whose sum is σ = 372715830. Its totient is φ = 99390880.

The previous prime is 198781757. The next prime is 198781769. The reversal of 198781768 is 867187891.

It is a happy number.

198781768 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 158306724 + 40475044 = 12582^2 + 6362^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (198781769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12423853 + ... + 12423868.

Almost surely, 2^198781768 is an apocalyptic number.

It is an amenable number.

198781768 is a deficient number, since it is larger than the sum of its proper divisors (173934062).

198781768 is a wasteful number, since it uses less digits than its factorization.

198781768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24847727 (or 24847723 counting only the distinct ones).

The product of its digits is 1354752, while the sum is 55.

The square root of 198781768 is about 14098.9988297042. The cubic root of 198781768 is about 583.6137512902.

The spelling of 198781768 in words is "one hundred ninety-eight million, seven hundred eighty-one thousand, seven hundred sixty-eight".