91198 has 4 divisors (see below), whose sum is σ = 136800. Its totient is φ = 45598.

The previous prime is 91193. The next prime is 91199. The reversal of 91198 is 89119.

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

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91193) by changing a digit.

91198 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22798 + ... + 22801.

It is an arithmetic number, because the mean of its divisors is an integer number (34200).

2⁹¹¹⁹⁸ is an apocalyptic number.

91198 is a deficient number, since it is larger than the sum of its proper divisors (45602).

91198 is a wasteful number, since it uses less digits than its factorization.

91198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45601.

The product of its digits is 648, while the sum is 28.

The square root of 91198 is about 301.9900660618. The cubic root of 91198 is about 45.0120132535.

It can be divided in two parts, 91 and 198, that added together give a square (289 = 17²).

The spelling of 91198 in words is "ninety-one thousand, one hundred ninety-eight".