685253636761 has 2 divisors, whose sum is σ = 685253636762. Its totient is φ = 685253636760.

The previous prime is 685253636723. The next prime is 685253636887. The reversal of 685253636761 is 167636352586.

685253636761 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 459438596761 + 225815040000 = 677819^2 + 475200^2 .

It is a cyclic number.

It is not a de Polignac number, because 685253636761 - 2¹⁷ = 685253505689 is a prime.

It is a super-2 number, since 2×685253636761² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 685253636696 and 685253636705.

It is not a weakly prime, because it can be changed into another prime (685253636261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342626818380 + 342626818381.

It is an arithmetic number, because the mean of its divisors is an integer number (342626818381).

Almost surely, 2^685253636761 is an apocalyptic number.

It is an amenable number.

685253636761 is a deficient number, since it is larger than the sum of its proper divisors (1).

685253636761 is an equidigital number, since it uses as much as digits as its factorization.

685253636761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32659200, while the sum is 58.

The spelling of 685253636761 in words is "six hundred eighty-five billion, two hundred fifty-three million, six hundred thirty-six thousand, seven hundred sixty-one".