66543005 has 4 divisors (see below), whose sum is σ = 79851612. Its totient is φ = 53234400.

The previous prime is 66542951. The next prime is 66543011. The reversal of 66543005 is 50034566.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50034566 = 2 ⋅25017283.

It can be written as a sum of positive squares in 2 ways, for example, as 16826404 + 49716601 = 4102^2 + 7051^2 .

It is not a de Polignac number, because 66543005 - 2¹² = 66538909 is a prime.

It is a Duffinian number.

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 3 ways as a sum of consecutive naturals, for example, 6654296 + ... + 6654305.

It is an arithmetic number, because the mean of its divisors is an integer number (19962903).

Almost surely, 2^66543005 is an apocalyptic number.

It is an amenable number.

66543005 is a deficient number, since it is larger than the sum of its proper divisors (13308607).

66543005 is a wasteful number, since it uses less digits than its factorization.

66543005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13308606.

The product of its (nonzero) digits is 10800, while the sum is 29.

The square root of 66543005 is about 8157.3895947172. The cubic root of 66543005 is about 405.2292661159.

The spelling of 66543005 in words is "sixty-six million, five hundred forty-three thousand, five".