66745543 has 4 divisors (see below), whose sum is σ = 66786048. Its totient is φ = 66705040.

The previous prime is 66745541. The next prime is 66745571. The reversal of 66745543 is 34554766.

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 66745543 - 2¹ = 66745541 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66745496 and 66745505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66745541) 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 3 ways as a sum of consecutive naturals, for example, 17671 + ... + 21112.

It is an arithmetic number, because the mean of its divisors is an integer number (16696512).

Almost surely, 2^66745543 is an apocalyptic number.

66745543 is a deficient number, since it is larger than the sum of its proper divisors (40505).

66745543 is a wasteful number, since it uses less digits than its factorization.

66745543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40504.

The product of its digits is 302400, while the sum is 40.

The square root of 66745543 is about 8169.7945506604. The cubic root of 66745543 is about 405.6399839432.

The spelling of 66745543 in words is "sixty-six million, seven hundred forty-five thousand, five hundred forty-three".