66766783 has 2 divisors, whose sum is σ = 66766784. Its totient is φ = 66766782.

The previous prime is 66766747. The next prime is 66766807. The reversal of 66766783 is 38766766.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66766783 - 2¹³ = 66758591 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66766283) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33383391 + 33383392.

It is an arithmetic number, because the mean of its divisors is an integer number (33383392).

Almost surely, 2^66766783 is an apocalyptic number.

66766783 is a deficient number, since it is larger than the sum of its proper divisors (1).

66766783 is an equidigital number, since it uses as much as digits as its factorization.

66766783 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1524096, while the sum is 49.

The square root of 66766783 is about 8171.0943575509. The cubic root of 66766783 is about 405.6830074377.

The spelling of 66766783 in words is "sixty-six million, seven hundred sixty-six thousand, seven hundred eighty-three".