Number of the day: 198445

Richard Dedekind was born on this day 186 years ago.

Properties of the number 198445:

198445 = 5 × 13 × 43 × 71 is the 180585^th composite number and is squarefree.
198445 has 4 distinct prime factors, 16 divisors, 39 antidivisors and 141120 totatives.
198445 has an emirp digit sum 31 in base 10.
Reversing the decimal digits of 198445 results in a semiprime.
198445 = 99223² - 99222² = 19847² - 19842² = 7639² - 7626² = 2329² - 2286² = 1559² - 1494² = 1433² - 1362² = 569² - 354² = 457² - 102² is the difference of 2 nonnegative squares in 8 ways.
198445 is the sum of 2 positive triangular numbers.
198445 is the difference of 2 positive pentagonal numbers in 7 ways.
198445 = 61² + 90² + 432² is the sum of 3 positive squares.
198445² = 119067² + 158756² = 48848² + 192339² = 100749² + 170968² = 76325² + 183180² is the sum of 2 positive squares in 4 ways.
198445² is the sum of 3 positive squares.
198445 is a proper divisor of 853¹² - 1.