1998717 has 8 divisors (see below), whose sum is σ = 3045696. Its totient is φ = 1142112.

The previous prime is 1998701. The next prime is 1998727. The reversal of 1998717 is 7178991.

It is a happy number.

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

It is not a de Polignac number, because 1998717 - 2⁴ = 1998701 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1998727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47568 + ... + 47609.

It is an arithmetic number, because the mean of its divisors is an integer number (380712).

2^1998717 is an apocalyptic number.

It is an amenable number.

1998717 is a deficient number, since it is larger than the sum of its proper divisors (1046979).

1998717 is an equidigital number, since it uses as much as digits as its factorization.

1998717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95187.

The product of its digits is 31752, while the sum is 42.

The square root of 1998717 is about 1413.7598806021. The cubic root of 1998717 is about 125.9651579147.

The spelling of 1998717 in words is "one million, nine hundred ninety-eight thousand, seven hundred seventeen".