686781738861120 has 2352 divisors, whose sum is σ = 3131525894871168. Its totient is φ = 139966566727680.

The previous prime is 686781738861109. The next prime is 686781738861121. The reversal of 686781738861120 is 21168837187686.

It is a happy number.

686781738861120 is a `hidden beast` number, since 6 + 8 + 67 + 8 + 1 + 7 + 388 + 61 + 120 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (686781738861121) by changing a digit.

It is a polite number, since it can be written in 335 ways as a sum of consecutive naturals, for example, 10021441255 + ... + 10021509785.

Almost surely, 2^{686781738861120} is an apocalyptic number.

686781738861120 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 686781738861120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1565762947435584).

686781738861120 is an abundant number, since it is smaller than the sum of its proper divisors (2444744156010048).

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

686781738861120 is a wasteful number, since it uses less digits than its factorization.

686781738861120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68628 (or 68584 counting only the distinct ones).

The product of its (nonzero) digits is 260112384, while the sum is 72.

The spelling of 686781738861120 in words is "six hundred eighty-six trillion, seven hundred eighty-one billion, seven hundred thirty-eight million, eight hundred sixty-one thousand, one hundred twenty".