81680506108 has 12 divisors (see below), whose sum is σ = 143246972232. Its totient is φ = 40752799760.

The previous prime is 81680506099. The next prime is 81680506153. The reversal of 81680506108 is 80160508618.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 21861223 + ... + 21864958.

It is an arithmetic number, because the mean of its divisors is an integer number (11937247686).

Almost surely, 2^81680506108 is an apocalyptic number.

It is an amenable number.

81680506108 is a deficient number, since it is larger than the sum of its proper divisors (61566466124).

81680506108 is a wasteful number, since it uses less digits than its factorization.

81680506108 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43726652 (or 43726650 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 43.

The spelling of 81680506108 in words is "eighty-one billion, six hundred eighty million, five hundred six thousand, one hundred eight".