9989879 has 2 divisors, whose sum is σ = 9989880.
Its totient is φ = 9989878.
The previous prime is 9989849. The next prime is 9989887. The reversal of 9989879 is 9789899.
It is a strong prime.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-9989879 is a prime.
It is a Sophie Germain prime.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (9989849) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4994939 + 4994940.
It is an arithmetic number, because the mean of its divisors is an integer number (4994940).
Almost surely, 29989879 is an apocalyptic number.
9989879 is a deficient number, since it is larger than the sum of its proper divisors (1).
9989879 is an equidigital number, since it uses as much as digits as its factorization.
9989879 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 2939328, while the sum is 59.
The square root of 9989879 is about 3160.6769844449.
The cubic root of 9989879 is about 215.3707610234.
The spelling of 9989879 in words is "nine million, nine hundred eighty-nine thousand, eight hundred seventy-nine".