81447181671 has 16 divisors (see below), whose sum is σ = 112129571840. Its totient is φ = 52532400960.

The previous prime is 81447181603. The next prime is 81447181691. The reversal of 81447181671 is 17618174418.

It is not a de Polignac number, because 81447181671 - 2¹⁴ = 81447165287 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81447181671.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81447181691) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 234336 + ... + 466698.

It is an arithmetic number, because the mean of its divisors is an integer number (7008098240).

Almost surely, 2^81447181671 is an apocalyptic number.

81447181671 is a deficient number, since it is larger than the sum of its proper divisors (30682390169).

81447181671 is a wasteful number, since it uses less digits than its factorization.

81447181671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 236166.

The product of its digits is 301056, while the sum is 48.

The spelling of 81447181671 in words is "eighty-one billion, four hundred forty-seven million, one hundred eighty-one thousand, six hundred seventy-one".