85666564699 has 2 divisors, whose sum is σ = 85666564700. Its totient is φ = 85666564698.

The previous prime is 85666564673. The next prime is 85666564721. The reversal of 85666564699 is 99646566658.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 85666564699 - 2⁹ = 85666564187 is a prime.

It is not a weakly prime, because it can be changed into another prime (85666564619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42833282349 + 42833282350.

It is an arithmetic number, because the mean of its divisors is an integer number (42833282350).

Almost surely, 2^85666564699 is an apocalyptic number.

85666564699 is a deficient number, since it is larger than the sum of its proper divisors (1).

85666564699 is an equidigital number, since it uses as much as digits as its factorization.

85666564699 is an evil number, because the sum of its binary digits is even.

The product of its digits is 503884800, while the sum is 70.

The spelling of 85666564699 in words is "eighty-five billion, six hundred sixty-six million, five hundred sixty-four thousand, six hundred ninety-nine".