9889999 has 4 divisors (see below), whose sum is σ = 11302864. Its totient is φ = 8477136.

The previous prime is 9889987. The next prime is 9890009. The reversal of 9889999 is 9999889.

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 9889999 - 2¹⁷ = 9758927 is a prime.

It is a Duffinian number.

9889999 is a modest number, since divided by 9999 gives 988 as remainder.

9889999 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9889909) 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, 706422 + ... + 706435.

It is an arithmetic number, because the mean of its divisors is an integer number (2825716).

Almost surely, 2^9889999 is an apocalyptic number.

9889999 is a deficient number, since it is larger than the sum of its proper divisors (1412865).

9889999 is a wasteful number, since it uses less digits than its factorization.

9889999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1412864.

The product of its digits is 3779136, while the sum is 61.

The square root of 9889999 is about 3144.8368797125. The cubic root of 9889999 is about 214.6505880327.

The spelling of 9889999 in words is "nine million, eight hundred eighty-nine thousand, nine hundred ninety-nine".