685736020571 has 4 divisors (see below), whose sum is σ = 783698309232. Its totient is φ = 587773731912.

The previous prime is 685736020451. The next prime is 685736020577. The reversal of 685736020571 is 175020637586.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-685736020571 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (685736020577) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48981144320 + ... + 48981144333.

It is an arithmetic number, because the mean of its divisors is an integer number (195924577308).

Almost surely, 2^685736020571 is an apocalyptic number.

685736020571 is a deficient number, since it is larger than the sum of its proper divisors (97962288661).

685736020571 is an equidigital number, since it uses as much as digits as its factorization.

685736020571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97962288660.

The product of its (nonzero) digits is 2116800, while the sum is 50.

The spelling of 685736020571 in words is "six hundred eighty-five billion, seven hundred thirty-six million, twenty thousand, five hundred seventy-one".