9998642 has 4 divisors (see below), whose sum is σ = 14997966. Its totient is φ = 4999320.

The previous prime is 9998641. The next prime is 9998689. The reversal of 9998642 is 2468999.

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., 5285401 + 4713241 = 2299^2 + 2171^2 .

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (9998641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2499659 + ... + 2499662.

Almost surely, 2^9998642 is an apocalyptic number.

9998642 is a deficient number, since it is larger than the sum of its proper divisors (4999324).

9998642 is a wasteful number, since it uses less digits than its factorization.

9998642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4999323.

The product of its digits is 279936, while the sum is 47.

The square root of 9998642 is about 3162.0629342251. The cubic root of 9998642 is about 215.4337161540.

The spelling of 9998642 in words is "nine million, nine hundred ninety-eight thousand, six hundred forty-two".