81947674886 has 64 divisors (see below), whose sum is σ = 154790355456. Its totient is φ = 31608921600.

The previous prime is 81947674843. The next prime is 81947674891. The reversal of 81947674886 is 68847674918.

It is a super-2 number, since 2×81947674886² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6414341 + ... + 6427103.

It is an arithmetic number, because the mean of its divisors is an integer number (2418599304).

Almost surely, 2^81947674886 is an apocalyptic number.

81947674886 is a deficient number, since it is larger than the sum of its proper divisors (72842680570).

81947674886 is a wasteful number, since it uses less digits than its factorization.

81947674886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13197.

The product of its digits is 130056192, while the sum is 68.

The spelling of 81947674886 in words is "eighty-one billion, nine hundred forty-seven million, six hundred seventy-four thousand, eight hundred eighty-six".