66872081571 has 4 divisors (see below), whose sum is σ = 89162775432. Its totient is φ = 44581387712.

The previous prime is 66872081537. The next prime is 66872081587. The reversal of 66872081571 is 17518027866.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66872081571 - 2⁷ = 66872081443 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66872081531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11145346926 + ... + 11145346931.

It is an arithmetic number, because the mean of its divisors is an integer number (22290693858).

Almost surely, 2^66872081571 is an apocalyptic number.

66872081571 is a deficient number, since it is larger than the sum of its proper divisors (22290693861).

66872081571 is a wasteful number, since it uses less digits than its factorization.

66872081571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22290693860.

The product of its (nonzero) digits is 1128960, while the sum is 51.

The spelling of 66872081571 in words is "sixty-six billion, eight hundred seventy-two million, eighty-one thousand, five hundred seventy-one".