66543273 has 6 divisors (see below), whose sum is σ = 96118074. Its totient is φ = 44362176.

The previous prime is 66543241. The next prime is 66543277. The reversal of 66543273 is 37234566.

It can be written as a sum of positive squares in only one way, i.e., 60652944 + 5890329 = 7788^2 + 2427^2 .

It is not a de Polignac number, because 66543273 - 2⁵ = 66543241 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66543277) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3696840 + ... + 3696857.

It is an arithmetic number, because the mean of its divisors is an integer number (16019679).

Almost surely, 2^66543273 is an apocalyptic number.

It is an amenable number.

66543273 is a deficient number, since it is larger than the sum of its proper divisors (29574801).

66543273 is a wasteful number, since it uses less digits than its factorization.

66543273 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7393703 (or 7393700 counting only the distinct ones).

The product of its digits is 90720, while the sum is 36.

The square root of 66543273 is about 8157.4060215242. The cubic root of 66543273 is about 405.2298101315.

The spelling of 66543273 in words is "sixty-six million, five hundred forty-three thousand, two hundred seventy-three".