685733251631 has 4 divisors (see below), whose sum is σ = 685743101592. Its totient is φ = 685723401672.

The previous prime is 685733251627. The next prime is 685733251639. The reversal of 685733251631 is 136152337586.

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

It is a cyclic number.

It is not a de Polignac number, because 685733251631 - 2² = 685733251627 is a prime.

It is a super-2 number, since 2×685733251631² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 685733251631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685733251639) 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, 4819805 + ... + 4960038.

It is an arithmetic number, because the mean of its divisors is an integer number (171435775398).

Almost surely, 2^685733251631 is an apocalyptic number.

685733251631 is a deficient number, since it is larger than the sum of its proper divisors (9849961).

685733251631 is an equidigital number, since it uses as much as digits as its factorization.

685733251631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9849960.

The product of its digits is 2721600, while the sum is 50.

The spelling of 685733251631 in words is "six hundred eighty-five billion, seven hundred thirty-three million, two hundred fifty-one thousand, six hundred thirty-one".