1998173 has 4 divisors (see below), whose sum is σ = 2103360. Its totient is φ = 1892988.

The previous prime is 1998169. The next prime is 1998181. The reversal of 1998173 is 3718991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 3718991 = 1459 ⋅2549.

It is a cyclic number.

It is not a de Polignac number, because 1998173 - 2² = 1998169 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1998133) 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, 52565 + ... + 52602.

It is an arithmetic number, because the mean of its divisors is an integer number (525840).

2^1998173 is an apocalyptic number.

It is an amenable number.

1998173 is a deficient number, since it is larger than the sum of its proper divisors (105187).

1998173 is a wasteful number, since it uses less digits than its factorization.

1998173 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105186.

The product of its digits is 13608, while the sum is 38.

The square root of 1998173 is about 1413.5674727440. The cubic root of 1998173 is about 125.9537287056.

The spelling of 1998173 in words is "one million, nine hundred ninety-eight thousand, one hundred seventy-three".