86669861 has 2 divisors, whose sum is σ = 86669862. Its totient is φ = 86669860.

The previous prime is 86669851. The next prime is 86669867. The reversal of 86669861 is 16896668.

86669861 is nontrivially palindromic in base 16.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 86136961 + 532900 = 9281^2 + 730^2 .

It is a cyclic number.

It is not a de Polignac number, because 86669861 - 2²² = 82475557 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (86669867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43334930 + 43334931.

It is an arithmetic number, because the mean of its divisors is an integer number (43334931).

Almost surely, 2^86669861 is an apocalyptic number.

It is an amenable number.

86669861 is a deficient number, since it is larger than the sum of its proper divisors (1).

86669861 is an equidigital number, since it uses as much as digits as its factorization.

86669861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 746496, while the sum is 50.

The square root of 86669861 is about 9309.6649241527. The cubic root of 86669861 is about 442.5435683319.

The spelling of 86669861 in words is "eighty-six million, six hundred sixty-nine thousand, eight hundred sixty-one".