66916771 has 2 divisors, whose sum is σ = 66916772. Its totient is φ = 66916770.

The previous prime is 66916769. The next prime is 66916781. The reversal of 66916771 is 17761966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66916771 - 2¹ = 66916769 is a prime.

Together with 66916769, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66916721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33458385 + 33458386.

It is an arithmetic number, because the mean of its divisors is an integer number (33458386).

Almost surely, 2^66916771 is an apocalyptic number.

66916771 is a deficient number, since it is larger than the sum of its proper divisors (1).

66916771 is an equidigital number, since it uses as much as digits as its factorization.

66916771 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 95256, while the sum is 43.

The square root of 66916771 is about 8180.2671716760. The cubic root of 66916771 is about 405.9865619566.

The spelling of 66916771 in words is "sixty-six million, nine hundred sixteen thousand, seven hundred seventy-one".