9998550 has 72 divisors (see below), whose sum is σ = 28464696. Its totient is φ = 2507520.

The previous prime is 9998543. The next prime is 9998557. The reversal of 9998550 is 558999.

9998550 is a `hidden beast` number, since 9 + 9 + 98 + 550 = 666.

It is an interprime number because it is at equal distance from previous prime (9998543) and next prime (9998557).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 9998496 and 9998505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9998557) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 6997 + ... + 8303.

It is an arithmetic number, because the mean of its divisors is an integer number (395343).

Almost surely, 2^9998550 is an apocalyptic number.

9998550 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 9998550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14232348).

9998550 is an abundant number, since it is smaller than the sum of its proper divisors (18466146).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9998550 is a wasteful number, since it uses less digits than its factorization.

9998550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1342 (or 1334 counting only the distinct ones).

The product of its (nonzero) digits is 145800, while the sum is 45.

The square root of 9998550 is about 3162.0483867266. The cubic root of 9998550 is about 215.4330553988.

The spelling of 9998550 in words is "nine million, nine hundred ninety-eight thousand, five hundred fifty".