85640356017869 has 2 divisors, whose sum is σ = 85640356017870. Its totient is φ = 85640356017868.

The previous prime is 85640356017859. The next prime is 85640356017899. The reversal of 85640356017869 is 96871065304658.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 79323729393769 + 6316626624100 = 8906387^2 + 2513290^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85640356017869 is a prime.

It is a super-2 number, since 2×85640356017869² (a number of 29 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 85640356017799 and 85640356017808.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85640356017809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42820178008934 + 42820178008935.

It is an arithmetic number, because the mean of its divisors is an integer number (42820178008935).

Almost surely, 2^{85640356017869} is an apocalyptic number.

It is an amenable number.

85640356017869 is a deficient number, since it is larger than the sum of its proper divisors (1).

85640356017869 is an equidigital number, since it uses as much as digits as its factorization.

85640356017869 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 261273600, while the sum is 68.

The spelling of 85640356017869 in words is "eighty-five trillion, six hundred forty billion, three hundred fifty-six million, seventeen thousand, eight hundred sixty-nine".