198172 has 24 divisors (see below), whose sum is σ = 387296. Its totient is φ = 88128.

The previous prime is 198139. The next prime is 198173. The reversal of 198172 is 271891.

198172 = T₃₃ + T₃₄ + ... + T₁₀₆.

It is an Ulam number.

It is a zygodrome in base 2.

It is a self number, because there is not a number n which added to its sum of digits gives 198172.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198173) by changing a digit.

198172 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1873 + ... + 1975.

2¹⁹⁸¹⁷² is an apocalyptic number.

It is an amenable number.

198172 is a deficient number, since it is larger than the sum of its proper divisors (189124).

198172 is a wasteful number, since it uses less digits than its factorization.

198172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157 (or 155 counting only the distinct ones).

The product of its digits is 1008, while the sum is 28.

The square root of 198172 is about 445.1651378983. The cubic root of 198172 is about 58.3016390184.

The spelling of 198172 in words is "one hundred ninety-eight thousand, one hundred seventy-two".