198908121 has 8 divisors (see below), whose sum is σ = 273766144. Its totient is φ = 128327760.

The previous prime is 198908119. The next prime is 198908123. The reversal of 198908121 is 121809891.

It is an interprime number because it is at equal distance from previous prime (198908119) and next prime (198908123).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 198908121 - 2¹ = 198908119 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 198908121.

It is not an unprimeable number, because it can be changed into a prime (198908123) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1069306 + ... + 1069491.

It is an arithmetic number, because the mean of its divisors is an integer number (34220768).

Almost surely, 2^198908121 is an apocalyptic number.

It is an amenable number.

198908121 is a deficient number, since it is larger than the sum of its proper divisors (74858023).

198908121 is a wasteful number, since it uses less digits than its factorization.

198908121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2138831.

The product of its (nonzero) digits is 10368, while the sum is 39.

The square root of 198908121 is about 14103.4790388755. The cubic root of 198908121 is about 583.7373805518.

The spelling of 198908121 in words is "one hundred ninety-eight million, nine hundred eight thousand, one hundred twenty-one".