66865273 has 4 divisors (see below), whose sum is σ = 66952548. Its totient is φ = 66778000.

The previous prime is 66865261. The next prime is 66865283. The reversal of 66865273 is 37256866.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 37256866 = 2 ⋅18628433.

It can be written as a sum of positive squares in 2 ways, for example, as 30769209 + 36096064 = 5547^2 + 6008^2 .

It is a cyclic number.

It is not a de Polignac number, because 66865273 - 2⁹ = 66864761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66865243) 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, 42478 + ... + 44023.

It is an arithmetic number, because the mean of its divisors is an integer number (16738137).

Almost surely, 2^66865273 is an apocalyptic number.

It is an amenable number.

66865273 is a deficient number, since it is larger than the sum of its proper divisors (87275).

66865273 is an equidigital number, since it uses as much as digits as its factorization.

66865273 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87274.

The product of its digits is 362880, while the sum is 43.

The square root of 66865273 is about 8177.1188691372. The cubic root of 66865273 is about 405.8823884622.

The spelling of 66865273 in words is "sixty-six million, eight hundred sixty-five thousand, two hundred seventy-three".