685207506811 has 2 divisors, whose sum is σ = 685207506812. Its totient is φ = 685207506810.

The previous prime is 685207506787. The next prime is 685207506817. The reversal of 685207506811 is 118605702586.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 685207506811 - 2¹¹ = 685207504763 is a prime.

It is a super-2 number, since 2×685207506811² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (685207506817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342603753405 + 342603753406.

It is an arithmetic number, because the mean of its divisors is an integer number (342603753406).

Almost surely, 2^685207506811 is an apocalyptic number.

685207506811 is a deficient number, since it is larger than the sum of its proper divisors (1).

685207506811 is an equidigital number, since it uses as much as digits as its factorization.

685207506811 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 806400, while the sum is 49.

The spelling of 685207506811 in words is "six hundred eighty-five billion, two hundred seven million, five hundred six thousand, eight hundred eleven".