9999785539878 has 32 divisors (see below), whose sum is σ = 20184073324800. Its totient is φ = 3302514563616.

The previous prime is 9999785539859. The next prime is 9999785539879. The reversal of 9999785539878 is 8789355879999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9999785539879) 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 15 ways as a sum of consecutive naturals, for example, 12915063 + ... + 13667421.

It is an arithmetic number, because the mean of its divisors is an integer number (630752291400).

Almost surely, 2^{9999785539878} is an apocalyptic number.

9999785539878 is an abundant number, since it is smaller than the sum of its proper divisors (10184287784922).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9999785539878 is a wasteful number, since it uses less digits than its factorization.

9999785539878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 772796.

The product of its digits is 111106598400, while the sum is 96.

The spelling of 9999785539878 in words is "nine trillion, nine hundred ninety-nine billion, seven hundred eighty-five million, five hundred thirty-nine thousand, eight hundred seventy-eight".