998121 has 8 divisors (see below), whose sum is σ = 1409184. Its totient is φ = 626240.

The previous prime is 998117. The next prime is 998147. The reversal of 998121 is 121899.

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

It is a cyclic number.

It is not a de Polignac number, because 998121 - 2² = 998117 is a prime.

It is not an unprimeable number, because it can be changed into a prime (998111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9735 + ... + 9836.

It is an arithmetic number, because the mean of its divisors is an integer number (176148).

2⁹⁹⁸¹²¹ is an apocalyptic number.

It is an amenable number.

998121 is a deficient number, since it is larger than the sum of its proper divisors (411063).

998121 is a wasteful number, since it uses less digits than its factorization.

998121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19591.

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

The square root of 998121 is about 999.0600582548. The cubic root of 998121 is about 99.9373273963.

The spelling of 998121 in words is "nine hundred ninety-eight thousand, one hundred twenty-one".