81856213076 has 24 divisors (see below), whose sum is σ = 156631891584. Its totient is φ = 37121431680.

The previous prime is 81856213067. The next prime is 81856213099. The reversal of 81856213076 is 67031265818.

It is a self number, because there is not a number n which added to its sum of digits gives 81856213076.

It is a congruent number.

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, 2129180 + ... + 2167283.

It is an arithmetic number, because the mean of its divisors is an integer number (6526328816).

Almost surely, 2^81856213076 is an apocalyptic number.

It is an amenable number.

81856213076 is a deficient number, since it is larger than the sum of its proper divisors (74775678508).

81856213076 is a wasteful number, since it uses less digits than its factorization.

81856213076 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4296911 (or 4296909 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 47.

The spelling of 81856213076 in words is "eighty-one billion, eight hundred fifty-six million, two hundred thirteen thousand, seventy-six".