9999989 has 4 divisors (see below), whose sum is σ = 10045056.
Its totient is φ = 9954924.
The previous prime is 9999973. The next prime is 9999991. The reversal of 9999989 is 9899999.
9999989 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.
It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.
It is a cyclic number.
It is not a de Polignac number, because 9999989 - 24 = 9999973 is a prime.
It is a Duffinian number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (9999929) 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, 22199 + ... + 22644.
It is an arithmetic number, because the mean of its divisors is an integer number (2511264).
Almost surely, 29999989 is an apocalyptic number.
It is an amenable number.
9999989 is a deficient number, since it is larger than the sum of its proper divisors (45067).
9999989 is a wasteful number, since it uses less digits than its factorization.
9999989 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 45066.
The product of its digits is 4251528, while the sum is 62.
The square root of 9999989 is about 3162.2759209152.
The cubic root of 9999989 is about 215.4433900072.
The spelling of 9999989 in words is "nine million, nine hundred ninety-nine thousand, nine hundred eighty-nine".