66544279 has 2 divisors, whose sum is σ = 66544280. Its totient is φ = 66544278.

The previous prime is 66544237. The next prime is 66544297. The reversal of 66544279 is 97244566.

It is a happy number.

Together with next prime (66544297) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66544279 - 2¹³ = 66536087 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66542279) 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 as a sum of consecutive naturals, namely, 33272139 + 33272140.

It is an arithmetic number, because the mean of its divisors is an integer number (33272140).

Almost surely, 2^66544279 is an apocalyptic number.

66544279 is a deficient number, since it is larger than the sum of its proper divisors (1).

66544279 is an equidigital number, since it uses as much as digits as its factorization.

66544279 is an odious number, because the sum of its binary digits is odd.

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

The square root of 66544279 is about 8157.4676830497. The cubic root of 66544279 is about 405.2318522068.

It can be divided in two parts, 665 and 44279, that added together give a palindrome (44944).

The spelling of 66544279 in words is "sixty-six million, five hundred forty-four thousand, two hundred seventy-nine".