198363891 has 36 divisors (see below), whose sum is σ = 304198664. Its totient is φ = 114882240.

The previous prime is 198363877. The next prime is 198363901.

198363891 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 198363891 - 2¹⁵ = 198331123 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 198363891.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198343891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 191511 + ... + 192543.

Almost surely, 2^198363891 is an apocalyptic number.

198363891 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

198363891 is a deficient number, since it is larger than the sum of its proper divisors (105834773).

198363891 is a wasteful number, since it uses less digits than its factorization.

198363891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1104 (or 1070 counting only the distinct ones).

The product of its digits is 279936, while the sum is 48.

The square root of 198363891 is about 14084.1716476334. The cubic root of 198363891 is about 583.2045087676.

The spelling of 198363891 in words is "one hundred ninety-eight million, three hundred sixty-three thousand, eight hundred ninety-one".