9991002023 has 4 divisors (see below), whose sum is σ = 9992653248. Its totient is φ = 9989350800.

The previous prime is 9991002013. The next prime is 9991002089. The reversal of 9991002023 is 3202001999.

9991002023 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9991002023 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 (9991002013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 816503 + ... + 828648.

It is an arithmetic number, because the mean of its divisors is an integer number (2498163312).

Almost surely, 2^9991002023 is an apocalyptic number.

9991002023 is a deficient number, since it is larger than the sum of its proper divisors (1651225).

9991002023 is a wasteful number, since it uses less digits than its factorization.

9991002023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1651224.

The product of its (nonzero) digits is 8748, while the sum is 35.

The square root of 9991002023 is about 99954.9999899955. Note that the first 4 decimals coincide. The cubic root of 9991002023 is about 2153.7883109967.

The spelling of 9991002023 in words is "nine billion, nine hundred ninety-one million, two thousand, twenty-three".