81271012154660 has 24 divisors (see below), whose sum is σ = 172586756152440. Its totient is φ = 32143141885184.

The previous prime is 81271012154581. The next prime is 81271012154677. The reversal of 81271012154660 is 6645121017218.

It can be written as a sum of positive squares in 4 ways, for example, as 13841688675364 + 67429323479296 = 3720442^2 + 8211536^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22828934219 + ... + 22828937778.

It is an arithmetic number, because the mean of its divisors is an integer number (7191114839685).

Almost surely, 2^{81271012154660} is an apocalyptic number.

It is an amenable number.

81271012154660 is an abundant number, since it is smaller than the sum of its proper divisors (91315743997780).

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

81271012154660 is a wasteful number, since it uses less digits than its factorization.

81271012154660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45657872095 (or 45657872093 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 44.

The spelling of 81271012154660 in words is "eighty-one trillion, two hundred seventy-one billion, twelve million, one hundred fifty-four thousand, six hundred sixty".