66558073 has 4 divisors (see below), whose sum is σ = 66659428. Its totient is φ = 66456720.

The previous prime is 66558071. The next prime is 66558101. The reversal of 66558073 is 37085566.

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 36385024 + 30173049 = 6032^2 + 5493^2 .

It is a cyclic number.

It is not a de Polignac number, because 66558073 - 2¹ = 66558071 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66558071) 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, 49686 + ... + 51007.

It is an arithmetic number, because the mean of its divisors is an integer number (16664857).

Almost surely, 2^66558073 is an apocalyptic number.

It is an amenable number.

66558073 is a deficient number, since it is larger than the sum of its proper divisors (101355).

66558073 is a wasteful number, since it uses less digits than its factorization.

66558073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101354.

The product of its (nonzero) digits is 151200, while the sum is 40.

The square root of 66558073 is about 8158.3131222085. The cubic root of 66558073 is about 405.2598505164.

The spelling of 66558073 in words is "sixty-six million, five hundred fifty-eight thousand, seventy-three".