85639837 has 2 divisors, whose sum is σ = 85639838. Its totient is φ = 85639836.

The previous prime is 85639811. The next prime is 85639909. The reversal of 85639837 is 73893658.

85639837 is nontrivially palindromic in base 15.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 85488516 + 151321 = 9246^2 + 389^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85639837 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85639237) 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, 42819918 + 42819919.

It is an arithmetic number, because the mean of its divisors is an integer number (42819919).

Almost surely, 2^85639837 is an apocalyptic number.

It is an amenable number.

85639837 is a deficient number, since it is larger than the sum of its proper divisors (1).

85639837 is an equidigital number, since it uses as much as digits as its factorization.

85639837 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1088640, while the sum is 49.

The square root of 85639837 is about 9254.1794341800. The cubic root of 85639837 is about 440.7834475143.

The spelling of 85639837 in words is "eighty-five million, six hundred thirty-nine thousand, eight hundred thirty-seven".