81708179185 has 16 divisors (see below), whose sum is σ = 98565667200. Its totient is φ = 65023531776.

The previous prime is 81708179141. The next prime is 81708179197. The reversal of 81708179185 is 58197180718.

It is a cyclic number.

It is not a de Polignac number, because 81708179185 - 2²⁵ = 81674624753 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 684486 + ... + 794944.

It is an arithmetic number, because the mean of its divisors is an integer number (6160354200).

Almost surely, 2^81708179185 is an apocalyptic number.

It is an amenable number.

81708179185 is a deficient number, since it is larger than the sum of its proper divisors (16857488015).

81708179185 is a wasteful number, since it uses less digits than its factorization.

81708179185 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111240.

The product of its (nonzero) digits is 1128960, while the sum is 55.

The spelling of 81708179185 in words is "eighty-one billion, seven hundred eight million, one hundred seventy-nine thousand, one hundred eighty-five".