9999659 has 2 divisors, whose sum is σ = 9999660. Its totient is φ = 9999658.

The previous prime is 9999653. The next prime is 9999667. The reversal of 9999659 is 9569999.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 9999659 - 2¹² = 9995563 is a prime.

It is not a weakly prime, because it can be changed into another prime (9999653) 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 as a sum of consecutive naturals, namely, 4999829 + 4999830.

It is an arithmetic number, because the mean of its divisors is an integer number (4999830).

Almost surely, 2^9999659 is an apocalyptic number.

9999659 is a deficient number, since it is larger than the sum of its proper divisors (1).

9999659 is an equidigital number, since it uses as much as digits as its factorization.

9999659 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1771470, while the sum is 56.

The square root of 9999659 is about 3162.2237428746. The cubic root of 9999659 is about 215.4410201013.

The spelling of 9999659 in words is "nine million, nine hundred ninety-nine thousand, six hundred fifty-nine".