198157 has 4 divisors (see below), whose sum is σ = 205020. Its totient is φ = 191296.

The previous prime is 198139. The next prime is 198173. The reversal of 198157 is 751891.

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

It can be written as a sum of positive squares in 2 ways, for example, as 60516 + 137641 = 246^2 + 371^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-198157 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

198157 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198127) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3388 + ... + 3445.

It is an arithmetic number, because the mean of its divisors is an integer number (51255).

2¹⁹⁸¹⁵⁷ is an apocalyptic number.

It is an amenable number.

198157 is a deficient number, since it is larger than the sum of its proper divisors (6863).

198157 is an equidigital number, since it uses as much as digits as its factorization.

198157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6862.

The product of its digits is 2520, while the sum is 31.

The square root of 198157 is about 445.1482898990. The cubic root of 198157 is about 58.3001679955.

The spelling of 198157 in words is "one hundred ninety-eight thousand, one hundred fifty-seven".