998555 has 8 divisors (see below), whose sum is σ = 1227744. Its totient is φ = 779200.

The previous prime is 998551. The next prime is 998561. The reversal of 998555 is 555899.

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 998555 - 2² = 998551 is a prime.

It is a super-2 number, since 2×998555² = 1994224176050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (998551) 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, 2231 + ... + 2640.

It is an arithmetic number, because the mean of its divisors is an integer number (153468).

2⁹⁹⁸⁵⁵⁵ is an apocalyptic number.

998555 is a deficient number, since it is larger than the sum of its proper divisors (229189).

998555 is a wasteful number, since it uses less digits than its factorization.

998555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4917.

The product of its digits is 81000, while the sum is 41.

The square root of 998555 is about 999.2772388081. The cubic root of 998555 is about 99.9518101144.

The spelling of 998555 in words is "nine hundred ninety-eight thousand, five hundred fifty-five".