9981898 has 4 divisors (see below), whose sum is σ = 14972850. Its totient is φ = 4990948.

The previous prime is 9981889. The next prime is 9981899. The reversal of 9981898 is 8981899.

9981898 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in only one way, i.e., 7601049 + 2380849 = 2757^2 + 1543^2 .

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (9981899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2495473 + ... + 2495476.

Almost surely, 2^9981898 is an apocalyptic number.

9981898 is a deficient number, since it is larger than the sum of its proper divisors (4990952).

9981898 is a wasteful number, since it uses less digits than its factorization.

9981898 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4990951.

The product of its digits is 373248, while the sum is 52.

The square root of 9981898 is about 3159.4141862060. The cubic root of 9981898 is about 215.3133918939.

Subtracting from 9981898 its reverse (8981899), we obtain a palindrome (999999).

The spelling of 9981898 in words is "nine million, nine hundred eighty-one thousand, eight hundred ninety-eight".