9998819 has 4 divisors (see below), whose sum is σ = 10011960. Its totient is φ = 9985680.

The previous prime is 9998809. The next prime is 9998851. The reversal of 9998819 is 9188999.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9188999 = 1609 ⋅5711.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9998819 is a prime.

It is a super-2 number, since 2×9998819² = 199952762789522, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9998809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5354 + ... + 6975.

It is an arithmetic number, because the mean of its divisors is an integer number (2502990).

Almost surely, 2^9998819 is an apocalyptic number.

9998819 is a deficient number, since it is larger than the sum of its proper divisors (13141).

9998819 is a wasteful number, since it uses less digits than its factorization.

9998819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13140.

The product of its digits is 419904, while the sum is 53.

The square root of 9998819 is about 3162.0909221589. The cubic root of 9998819 is about 215.4349873781.

The spelling of 9998819 in words is "nine million, nine hundred ninety-eight thousand, eight hundred nineteen".