191898 has 24 divisors (see below), whose sum is σ = 475488. Its totient is φ = 54792.

The previous prime is 191861. The next prime is 191899. The reversal of 191898 is 898191.

It is a Curzon number.

It is a nialpdrome in base 9.

It is not an unprimeable number, because it can be changed into a prime (191899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 636 + ... + 887.

It is an arithmetic number, because the mean of its divisors is an integer number (19812).

2¹⁹¹⁸⁹⁸ is an apocalyptic number.

191898 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

191898 is an abundant number, since it is smaller than the sum of its proper divisors (283590).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

191898 is a wasteful number, since it uses less digits than its factorization.

191898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1538 (or 1535 counting only the distinct ones).

The product of its digits is 5184, while the sum is 36.

The square root of 191898 is about 438.0616394984. The cubic root of 191898 is about 57.6797650682.

It can be divided in two parts, 1918 and 98, that added together give a triangular number (2016 = T₆₃).

The spelling of 191898 in words is "one hundred ninety-one thousand, eight hundred ninety-eight".