121998 has 8 divisors (see below), whose sum is σ = 244008. Its totient is φ = 40664.

The previous prime is 121997. The next prime is 122011. The reversal of 121998 is 899121.

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

121998 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121993) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10161 + ... + 10172.

It is an arithmetic number, because the mean of its divisors is an integer number (30501).

2¹²¹⁹⁹⁸ is an apocalyptic number.

121998 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

121998 is a wasteful number, since it uses less digits than its factorization.

121998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20338.

The product of its digits is 1296, while the sum is 30.

The square root of 121998 is about 349.2821209281. The cubic root of 121998 is about 49.5964856164.

The spelling of 121998 in words is "one hundred twenty-one thousand, nine hundred ninety-eight".