66667279 has 4 divisors (see below), whose sum is σ = 76191184. Its totient is φ = 57143376.

The previous prime is 66667277. The next prime is 66667283. The reversal of 66667279 is 97276666.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66667279 - 2¹ = 66667277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66667277) 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, 4761942 + ... + 4761955.

It is an arithmetic number, because the mean of its divisors is an integer number (19047796).

Almost surely, 2^66667279 is an apocalyptic number.

66667279 is a deficient number, since it is larger than the sum of its proper divisors (9523905).

66667279 is an equidigital number, since it uses as much as digits as its factorization.

66667279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9523904.

The product of its digits is 1143072, while the sum is 49.

The square root of 66667279 is about 8165.0033067966. The cubic root of 66667279 is about 405.4813744794.

The spelling of 66667279 in words is "sixty-six million, six hundred sixty-seven thousand, two hundred seventy-nine".