198951 has 16 divisors (see below), whose sum is σ = 290304. Its totient is φ = 120704.

The previous prime is 198943. The next prime is 198953. The reversal of 198951 is 159891.

It is a cyclic number.

It is not a de Polignac number, because 198951 - 2³ = 198943 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198953) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2356 + ... + 2438.

It is an arithmetic number, because the mean of its divisors is an integer number (18144).

2¹⁹⁸⁹⁵¹ is an apocalyptic number.

198951 is a deficient number, since it is larger than the sum of its proper divisors (91353).

198951 is a wasteful number, since it uses less digits than its factorization.

198951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150.

The product of its digits is 3240, while the sum is 33.

The square root of 198951 is about 446.0392359423. The cubic root of 198951 is about 58.3779323329.

Subtracting from 198951 its reverse (159891), we obtain a triangular number (39060 = T₂₇₉).

The spelling of 198951 in words is "one hundred ninety-eight thousand, nine hundred fifty-one".