99999999991868 has 24 divisors (see below), whose sum is σ = 175317620529744. Its totient is φ = 49909276368000.

The previous prime is 99999999991867. The next prime is 99999999991877. The reversal of 99999999991868 is 86819999999999.

It is a super-2 number, since 2×99999999991868² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99999999991867) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12821603 + ... + 19089093.

It is an arithmetic number, because the mean of its divisors is an integer number (7304900855406).

Almost surely, 2^{99999999991868} is an apocalyptic number.

It is an amenable number.

99999999991868 is a deficient number, since it is larger than the sum of its proper divisors (75317620537876).

99999999991868 is a wasteful number, since it uses less digits than its factorization.

99999999991868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6274733 (or 6274731 counting only the distinct ones).

The product of its digits is 1338925209984, while the sum is 113.

The spelling of 99999999991868 in words is "ninety-nine trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-one thousand, eight hundred sixty-eight".