66543793 has 4 divisors (see below), whose sum is σ = 66566500. Its totient is φ = 66521088.

The previous prime is 66543791. The next prime is 66543811. The reversal of 66543793 is 39734566.

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

It can be written as a sum of positive squares in 2 ways, for example, as 22014864 + 44528929 = 4692^2 + 6673^2 .

It is a cyclic number.

It is not a de Polignac number, because 66543793 - 2¹ = 66543791 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66543791) 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, 6168 + ... + 13081.

It is an arithmetic number, because the mean of its divisors is an integer number (16641625).

Almost surely, 2^66543793 is an apocalyptic number.

It is an amenable number.

66543793 is a deficient number, since it is larger than the sum of its proper divisors (22707).

66543793 is a wasteful number, since it uses less digits than its factorization.

66543793 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22706.

The product of its digits is 408240, while the sum is 43.

The square root of 66543793 is about 8157.4378943391. The cubic root of 66543793 is about 405.2308656799.

The spelling of 66543793 in words is "sixty-six million, five hundred forty-three thousand, seven hundred ninety-three".