9899966 has 4 divisors (see below), whose sum is σ = 14849952. Its totient is φ = 4949982.

The previous prime is 9899963. The next prime is 9899977. The reversal of 9899966 is 6699989.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9899963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2474990 + ... + 2474993.

It is an arithmetic number, because the mean of its divisors is an integer number (3712488).

Almost surely, 2^9899966 is an apocalyptic number.

9899966 is a deficient number, since it is larger than the sum of its proper divisors (4949986).

9899966 is a wasteful number, since it uses less digits than its factorization.

9899966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4949985.

The product of its digits is 1889568, while the sum is 56.

The square root of 9899966 is about 3146.4211415511. The cubic root of 9899966 is about 214.7226710909.

The spelling of 9899966 in words is "nine million, eight hundred ninety-nine thousand, nine hundred sixty-six".