81927681206 has 24 divisors (see below), whose sum is σ = 147566915136. Its totient is φ = 33979221360.

The previous prime is 81927681179. The next prime is 81927681221. The reversal of 81927681206 is 60218672918.

It is a super-2 number, since 2×81927681206² (a number of 23 digits) contains 22 as substring.

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 11 ways as a sum of consecutive naturals, for example, 13480781 + ... + 13486856.

It is an arithmetic number, because the mean of its divisors is an integer number (6148621464).

Almost surely, 2^81927681206 is an apocalyptic number.

81927681206 is a deficient number, since it is larger than the sum of its proper divisors (65639233930).

81927681206 is a wasteful number, since it uses less digits than its factorization.

81927681206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26967684 (or 26967677 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 50.

The spelling of 81927681206 in words is "eighty-one billion, nine hundred twenty-seven million, six hundred eighty-one thousand, two hundred six".