9991803 has 8 divisors (see below), whose sum is σ = 13392208. Its totient is φ = 6626304.

The previous prime is 9991771. The next prime is 9991811. The reversal of 9991803 is 3081999.

9991803 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 9991803 - 2⁵ = 9991771 is a prime.

It is a super-2 number, since 2×9991803² = 199672254381618, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9991603) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8050 + ... + 9207.

It is an arithmetic number, because the mean of its divisors is an integer number (1674026).

Almost surely, 2^9991803 is an apocalyptic number.

9991803 is a deficient number, since it is larger than the sum of its proper divisors (3400405).

9991803 is a wasteful number, since it uses less digits than its factorization.

9991803 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17453.

The product of its (nonzero) digits is 17496, while the sum is 39.

The square root of 9991803 is about 3160.9813349655. The cubic root of 9991803 is about 215.3845865744.

The spelling of 9991803 in words is "nine million, nine hundred ninety-one thousand, eight hundred three".