81671988886 has 8 divisors (see below), whose sum is σ = 122509237824. Its totient is φ = 40835576280.

The previous prime is 81671988821. The next prime is 81671988901. The reversal of 81671988886 is 68888917618.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-3 number, since 3×81671988886³ (a number of 34 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 179476 + ... + 442216.

It is an arithmetic number, because the mean of its divisors is an integer number (15313654728).

Almost surely, 2^81671988886 is an apocalyptic number.

81671988886 is a deficient number, since it is larger than the sum of its proper divisors (40837248938).

81671988886 is a wasteful number, since it uses less digits than its factorization.

81671988886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418166.

The product of its digits is 74317824, while the sum is 70.

The spelling of 81671988886 in words is "eighty-one billion, six hundred seventy-one million, nine hundred eighty-eight thousand, eight hundred eighty-six".