81168478120 has 32 divisors (see below), whose sum is σ = 193371964200. Its totient is φ = 30557544448.

The previous prime is 81168478117. The next prime is 81168478121. The reversal of 81168478120 is 2187486118.

It can be written as a sum of positive squares in 4 ways, for example, as 81155474884 + 13003236 = 284878^2 + 3606^2 .

It is not an unprimeable number, because it can be changed into a prime (81168478121) 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 7 ways as a sum of consecutive naturals, for example, 59682025 + ... + 59683384.

Almost surely, 2^81168478120 is an apocalyptic number.

It is an amenable number.

81168478120 is an abundant number, since it is smaller than the sum of its proper divisors (112203486080).

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

81168478120 is a wasteful number, since it uses less digits than its factorization.

81168478120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119365437 (or 119365433 counting only the distinct ones).

The product of its (nonzero) digits is 172032, while the sum is 46.

The spelling of 81168478120 in words is "eighty-one billion, one hundred sixty-eight million, four hundred seventy-eight thousand, one hundred twenty".