999999999999988 has 24 divisors (see below), whose sum is σ = 1995475113123912. Its totient is φ = 434389140271104.

The previous prime is 999999999999947. The next prime is 999999999999989. The reversal of 999999999999988 is 889999999999999.

It can be written as a sum of positive squares in 4 ways, for example, as 117405503085924 + 882594496914064 = 10835382^2 + 29708492^2 .

It is a super-9 number, since 9×999999999999988⁹ (a number of 136 digits) contains 999999999 as substring.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999999999999989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 565610858845 + ... + 565610860612.

It is an arithmetic number, because the mean of its divisors is an integer number (83144796380163).

Almost surely, 2^{999999999999988} is an apocalyptic number.

It is an amenable number.

999999999999988 is a deficient number, since it is larger than the sum of its proper divisors (995475113123924).

999999999999988 is a wasteful number, since it uses less digits than its factorization.

999999999999988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1131221719491 (or 1131221719489 counting only the distinct ones).

The product of its digits is 162679413013056, while the sum is 133.

The spelling of 999999999999988 in words is "nine hundred ninety-nine trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred eighty-eight".