998131 has 4 divisors (see below), whose sum is σ = 1041552. Its totient is φ = 954712.

The previous prime is 998117. The next prime is 998147. The reversal of 998131 is 131899.

998131 is nontrivially palindromic in base 8.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 998131 - 2¹³ = 989939 is a prime.

It is a super-2 number, since 2×998131² = 1992530986322, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

998131 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 998093 and 998102.

It is not an unprimeable number, because it can be changed into a prime (998111) 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, 21676 + ... + 21721.

It is an arithmetic number, because the mean of its divisors is an integer number (260388).

2⁹⁹⁸¹³¹ is an apocalyptic number.

998131 is a deficient number, since it is larger than the sum of its proper divisors (43421).

998131 is a wasteful number, since it uses less digits than its factorization.

998131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43420.

The product of its digits is 1944, while the sum is 31.

The square root of 998131 is about 999.0650629464. The cubic root of 998131 is about 99.9376611467.

The spelling of 998131 in words is "nine hundred ninety-eight thousand, one hundred thirty-one".