686742159816 has 256 divisors, whose sum is σ = 2000829600000. Its totient is φ = 218047334400.

The previous prime is 686742159809. The next prime is 686742159847. The reversal of 686742159816 is 618951247686.

686742159816 is a `hidden beast` number, since 6 + 8 + 6 + 7 + 4 + 21 + 598 + 16 = 666.

It is a super-2 number, since 2×686742159816² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 77848686 + ... + 77857506.

It is an arithmetic number, because the mean of its divisors is an integer number (7815740625).

Almost surely, 2^686742159816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686742159816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1000414800000).

686742159816 is an abundant number, since it is smaller than the sum of its proper divisors (1314087440184).

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

686742159816 is a wasteful number, since it uses less digits than its factorization.

686742159816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9085 (or 9075 counting only the distinct ones).

The product of its digits is 34836480, while the sum is 63.

The spelling of 686742159816 in words is "six hundred eighty-six billion, seven hundred forty-two million, one hundred fifty-nine thousand, eight hundred sixteen".