198661745 has 32 divisors (see below), whose sum is σ = 264539520. Its totient is φ = 142535680.

The previous prime is 198661721. The next prime is 198661753. The reversal of 198661745 is 547166891.

It is a de Polignac number, because none of the positive numbers 2^k-198661745 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 198661745.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 204110 + ... + 205080.

It is an arithmetic number, because the mean of its divisors is an integer number (8266860).

Almost surely, 2^198661745 is an apocalyptic number.

It is an amenable number.

198661745 is a deficient number, since it is larger than the sum of its proper divisors (65877775).

198661745 is a wasteful number, since it uses less digits than its factorization.

198661745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1105.

The product of its digits is 362880, while the sum is 47.

The square root of 198661745 is about 14094.7417500286. The cubic root of 198661745 is about 583.4962670483.

The spelling of 198661745 in words is "one hundred ninety-eight million, six hundred sixty-one thousand, seven hundred forty-five".