66065543 has 4 divisors (see below), whose sum is σ = 66430728. Its totient is φ = 65700360.

The previous prime is 66065533. The next prime is 66065569. The reversal of 66065543 is 34556066.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34556066 = 2 ⋅17278033.

It is a cyclic number.

It is not a de Polignac number, because 66065543 - 2¹⁰ = 66064519 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 (66065513) 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, 182321 + ... + 182682.

It is an arithmetic number, because the mean of its divisors is an integer number (16607682).

Almost surely, 2^66065543 is an apocalyptic number.

66065543 is a deficient number, since it is larger than the sum of its proper divisors (365185).

66065543 is a wasteful number, since it uses less digits than its factorization.

66065543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365184.

The product of its (nonzero) digits is 64800, while the sum is 35.

The square root of 66065543 is about 8128.0712964393. The cubic root of 66065543 is about 404.2577330535.

The spelling of 66065543 in words is "sixty-six million, sixty-five thousand, five hundred forty-three".