66942979 has 2 divisors, whose sum is σ = 66942980. Its totient is φ = 66942978.

The previous prime is 66942977. The next prime is 66943021. The reversal of 66942979 is 97924966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66942979 - 2¹ = 66942977 is a prime.

Together with 66942977, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66942973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33471489 + 33471490.

It is an arithmetic number, because the mean of its divisors is an integer number (33471490).

Almost surely, 2^66942979 is an apocalyptic number.

66942979 is a deficient number, since it is larger than the sum of its proper divisors (1).

66942979 is an equidigital number, since it uses as much as digits as its factorization.

66942979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1469664, while the sum is 52.

The square root of 66942979 is about 8181.8689185296. The cubic root of 66942979 is about 406.0395566788.

The spelling of 66942979 in words is "sixty-six million, nine hundred forty-two thousand, nine hundred seventy-nine".