9986819 has 4 divisors (see below), whose sum is σ = 10135944. Its totient is φ = 9837696.

The previous prime is 9986813. The next prime is 9986831. The reversal of 9986819 is 9186899.

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

It is a cyclic number.

It is not a de Polignac number, because 9986819 - 2⁸ = 9986563 is a prime.

It is a super-2 number, since 2×9986819² = 199473107477522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9986813) 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, 74462 + ... + 74595.

It is an arithmetic number, because the mean of its divisors is an integer number (2533986).

Almost surely, 2^9986819 is an apocalyptic number.

9986819 is a deficient number, since it is larger than the sum of its proper divisors (149125).

9986819 is a wasteful number, since it uses less digits than its factorization.

9986819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149124.

The product of its digits is 279936, while the sum is 50.

The square root of 9986819 is about 3160.1928738607. The cubic root of 9986819 is about 215.3487687040.

The spelling of 9986819 in words is "nine million, nine hundred eighty-six thousand, eight hundred nineteen".