81571711382 has 16 divisors (see below), whose sum is σ = 142475658912. Its totient is φ = 34299695040.

The previous prime is 81571711379. The next prime is 81571711409. The reversal of 81571711382 is 28311717518.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54966719 + ... + 54968202.

It is an arithmetic number, because the mean of its divisors is an integer number (8904728682).

Almost surely, 2^81571711382 is an apocalyptic number.

81571711382 is a deficient number, since it is larger than the sum of its proper divisors (60903947530).

81571711382 is a wasteful number, since it uses less digits than its factorization.

81571711382 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109934983.

The product of its digits is 94080, while the sum is 44.

The spelling of 81571711382 in words is "eighty-one billion, five hundred seventy-one million, seven hundred eleven thousand, three hundred eighty-two".