9998531 has 4 divisors (see below), whose sum is σ = 10005864. Its totient is φ = 9991200.

The previous prime is 9998479. The next prime is 9998539. The reversal of 9998531 is 1358999.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1358999 = 241 ⋅5639.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9998531 is a prime.

It is a super-2 number, since 2×9998531² = 199941244315922, which contains 22 as substring.

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 (9998539) 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, 950 + ... + 4571.

It is an arithmetic number, because the mean of its divisors is an integer number (2501466).

Almost surely, 2^9998531 is an apocalyptic number.

9998531 is a deficient number, since it is larger than the sum of its proper divisors (7333).

9998531 is a wasteful number, since it uses less digits than its factorization.

9998531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7332.

The product of its digits is 87480, while the sum is 44.

The square root of 9998531 is about 3162.0453823435. The cubic root of 9998531 is about 215.4329189380.

The spelling of 9998531 in words is "nine million, nine hundred ninety-eight thousand, five hundred thirty-one".