685946072729 has 4 divisors (see below), whose sum is σ = 686504207460. Its totient is φ = 685387938000.

The previous prime is 685946072723. The next prime is 685946072741. The reversal of 685946072729 is 927270649586.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 927270649586 = 2 ⋅463635324793.

It can be written as a sum of positive squares in 2 ways, for example, as 608899302400 + 77046770329 = 780320^2 + 277573^2 .

It is a cyclic number.

It is not a de Polignac number, because 685946072729 - 2²⁸ = 685677637273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (685946072723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 279065522 + ... + 279067979.

It is an arithmetic number, because the mean of its divisors is an integer number (171626051865).

Almost surely, 2^685946072729 is an apocalyptic number.

It is an amenable number.

685946072729 is a deficient number, since it is larger than the sum of its proper divisors (558134731).

685946072729 is a wasteful number, since it uses less digits than its factorization.

685946072729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 558134730.

The product of its (nonzero) digits is 91445760, while the sum is 65.

The spelling of 685946072729 in words is "six hundred eighty-five billion, nine hundred forty-six million, seventy-two thousand, seven hundred twenty-nine".