685866555000 has 1280 divisors, whose sum is σ = 2779030425600. Its totient is φ = 155010240000.

The previous prime is 685866554833. The next prime is 685866555029. The reversal of 685866555000 is 555668586.

685866555000 is a `hidden beast` number, since 6 + 8 + 5 + 86 + 6 + 5 + 550 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 319 ways as a sum of consecutive naturals, for example, 1468664767 + ... + 1468665233.

It is an arithmetic number, because the mean of its divisors is an integer number (2171117520).

Almost surely, 2^685866555000 is an apocalyptic number.

685866555000 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 685866555000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1389515212800).

685866555000 is an abundant number, since it is smaller than the sum of its proper divisors (2093163870600).

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

685866555000 is a wasteful number, since it uses less digits than its factorization.

685866555000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 579 (or 554 counting only the distinct ones).

The product of its (nonzero) digits is 8640000, while the sum is 54.

The spelling of 685866555000 in words is "six hundred eighty-five billion, eight hundred sixty-six million, five hundred fifty-five thousand".