9999988806 has 32 divisors (see below), whose sum is σ = 21378567168. Its totient is φ = 3110634560.

The previous prime is 9999988769. The next prime is 9999988807. The reversal of 9999988806 is 6088899999.

It is a super-2 number, since 2×9999988806² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9999988807) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 878046 + ... + 889361.

It is an arithmetic number, because the mean of its divisors is an integer number (668080224).

Almost surely, 2^9999988806 is an apocalyptic number.

9999988806 is an abundant number, since it is smaller than the sum of its proper divisors (11378578362).

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

9999988806 is a wasteful number, since it uses less digits than its factorization.

9999988806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1767476.

The product of its (nonzero) digits is 181398528, while the sum is 75.

The square root of 9999988806 is about 99999.9440299843. The cubic root of 9999988806 is about 2154.4338861402.

It can be divided in two parts, 99999 and 88806, that added together give a triangular number (188805 = T₆₁₄).

The spelling of 9999988806 in words is "nine billion, nine hundred ninety-nine million, nine hundred eighty-eight thousand, eight hundred six".