82021666537571 has 8 divisors (see below), whose sum is σ = 85622888618784. Its totient is φ = 78423366345280.

The previous prime is 82021666537553. The next prime is 82021666537597. The reversal of 82021666537571 is 17573566612028.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-82021666537571 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 82021666537571.

It is not an unprimeable number, because it can be changed into a prime (82021666537171) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 730414856 + ... + 730527141.

It is an arithmetic number, because the mean of its divisors is an integer number (10702861077348).

Almost surely, 2^{82021666537571} is an apocalyptic number.

82021666537571 is a deficient number, since it is larger than the sum of its proper divisors (3601222081213).

82021666537571 is a wasteful number, since it uses less digits than its factorization.

82021666537571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1460944461.

The product of its (nonzero) digits is 25401600, while the sum is 59.

The spelling of 82021666537571 in words is "eighty-two trillion, twenty-one billion, six hundred sixty-six million, five hundred thirty-seven thousand, five hundred seventy-one".