85646542789 has 2 divisors, whose sum is σ = 85646542790. Its totient is φ = 85646542788.

The previous prime is 85646542781. The next prime is 85646542823. The reversal of 85646542789 is 98724564658.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78605654689 + 7040888100 = 280367^2 + 83910^2 .

It is a cyclic number.

It is not a de Polignac number, because 85646542789 - 2³ = 85646542781 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 85646542789.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85646542781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42823271394 + 42823271395.

It is an arithmetic number, because the mean of its divisors is an integer number (42823271395).

Almost surely, 2^85646542789 is an apocalyptic number.

It is an amenable number.

85646542789 is a deficient number, since it is larger than the sum of its proper divisors (1).

85646542789 is an equidigital number, since it uses as much as digits as its factorization.

85646542789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 116121600, while the sum is 64.

The spelling of 85646542789 in words is "eighty-five billion, six hundred forty-six million, five hundred forty-two thousand, seven hundred eighty-nine".