85723939309 has 2 divisors, whose sum is σ = 85723939310. Its totient is φ = 85723939308.

The previous prime is 85723939297. The next prime is 85723939337. The reversal of 85723939309 is 90393932758.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84311833225 + 1412106084 = 290365^2 + 37578^2 .

It is a cyclic number.

It is not a de Polignac number, because 85723939309 - 2⁷ = 85723939181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85723939409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42861969654 + 42861969655.

It is an arithmetic number, because the mean of its divisors is an integer number (42861969655).

Almost surely, 2^85723939309 is an apocalyptic number.

It is an amenable number.

85723939309 is a deficient number, since it is larger than the sum of its proper divisors (1).

85723939309 is an equidigital number, since it uses as much as digits as its factorization.

85723939309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11022480, while the sum is 58.

The spelling of 85723939309 in words is "eighty-five billion, seven hundred twenty-three million, nine hundred thirty-nine thousand, three hundred nine".