66543345 has 60 divisors (see below), whose sum is σ = 128131380. Its totient is φ = 31944000.

The previous prime is 66543311. The next prime is 66543349. The reversal of 66543345 is 54334566.

It can be written as a sum of positive squares in 2 ways, for example, as 47568609 + 18974736 = 6897^2 + 4356^2 .

It is not a de Polignac number, because 66543345 - 2¹⁰ = 66542321 is a prime.

Its product of digits (129600) is a multiple of the sum of its prime divisors (120).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66543349) by changing a digit.

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 59 ways as a sum of consecutive naturals, for example, 658795 + ... + 658895.

It is an arithmetic number, because the mean of its divisors is an integer number (2135523).

Almost surely, 2^66543345 is an apocalyptic number.

It is an amenable number.

66543345 is a deficient number, since it is larger than the sum of its proper divisors (61588035).

66543345 is a wasteful number, since it uses less digits than its factorization.

66543345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156 (or 120 counting only the distinct ones).

The product of its digits is 129600, while the sum is 36.

The square root of 66543345 is about 8157.4104346907. The cubic root of 66543345 is about 405.2299562847.

It can be divided in two parts, 6654 and 3345, that added together give a palindrome (9999).

The spelling of 66543345 in words is "sixty-six million, five hundred forty-three thousand, three hundred forty-five".