685824311440 has 40 divisors (see below), whose sum is σ = 1609170365880. Its totient is φ = 271812934656.

The previous prime is 685824311399. The next prime is 685824311441. The reversal of 685824311440 is 44113428586.

It can be written as a sum of positive squares in 4 ways, for example, as 142932388096 + 542891923344 = 378064^2 + 736812^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×685824311440² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (685824311441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39316069 + ... + 39333508.

It is an arithmetic number, because the mean of its divisors is an integer number (40229259147).

Almost surely, 2^685824311440 is an apocalyptic number.

It is an amenable number.

685824311440 is an abundant number, since it is smaller than the sum of its proper divisors (923346054440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

685824311440 is a wasteful number, since it uses less digits than its factorization.

685824311440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78649699 (or 78649693 counting only the distinct ones).

The product of its (nonzero) digits is 737280, while the sum is 46.

The spelling of 685824311440 in words is "six hundred eighty-five billion, eight hundred twenty-four million, three hundred eleven thousand, four hundred forty".