9998100091 has 24 divisors (see below), whose sum is σ = 11837760000. Its totient is φ = 8418153744.

The previous prime is 9998100083. The next prime is 9998100097. The reversal of 9998100091 is 1900018999.

It is not a de Polignac number, because 9998100091 - 2³ = 9998100083 is a prime.

It is the 99991-st Hogben number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9998100097) by changing a digit.

It is a nontrivial repunit in base 99990.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 763840 + ... + 776818.

It is an arithmetic number, because the mean of its divisors is an integer number (493240000).

Almost surely, 2^9998100091 is an apocalyptic number.

9998100091 is a deficient number, since it is larger than the sum of its proper divisors (1839659909).

9998100091 is a wasteful number, since it uses less digits than its factorization.

9998100091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13271 (or 13264 counting only the distinct ones).

The product of its (nonzero) digits is 52488, while the sum is 46.

The square root of 9998100091 is about 99990.5000037504. The cubic root of 9998100091 is about 2154.2982403949.

The spelling of 9998100091 in words is "nine billion, nine hundred ninety-eight million, one hundred thousand, ninety-one".