66859967 has 2 divisors, whose sum is σ = 66859968. Its totient is φ = 66859966.

The previous prime is 66859957. The next prime is 66859987. The reversal of 66859967 is 76995866.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66859967 - 2⁴ = 66859951 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66859937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33429983 + 33429984.

It is an arithmetic number, because the mean of its divisors is an integer number (33429984).

Almost surely, 2^66859967 is an apocalyptic number.

66859967 is a deficient number, since it is larger than the sum of its proper divisors (1).

66859967 is an equidigital number, since it uses as much as digits as its factorization.

66859967 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4898880, while the sum is 56.

The square root of 66859967 is about 8176.7944207984. The cubic root of 66859967 is about 405.8716521022.

The spelling of 66859967 in words is "sixty-six million, eight hundred fifty-nine thousand, nine hundred sixty-seven".