66150543791 has 4 divisors (see below), whose sum is σ = 66556375512. Its totient is φ = 65744712072.

The previous prime is 66150543713. The next prime is 66150543817. The reversal of 66150543791 is 19734505166.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19734505166 = 2 ⋅9867252583.

It is a cyclic number.

It is not a de Polignac number, because 66150543791 - 2¹⁰ = 66150542767 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66150543091) 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, 202915616 + ... + 202915941.

It is an arithmetic number, because the mean of its divisors is an integer number (16639093878).

Almost surely, 2^66150543791 is an apocalyptic number.

66150543791 is a deficient number, since it is larger than the sum of its proper divisors (405831721).

66150543791 is a wasteful number, since it uses less digits than its factorization.

66150543791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 405831720.

The product of its (nonzero) digits is 680400, while the sum is 47.

The spelling of 66150543791 in words is "sixty-six billion, one hundred fifty million, five hundred forty-three thousand, seven hundred ninety-one".