687647315995920 has 1280 divisors, whose sum is σ = 2792125566812160. Its totient is φ = 152299516723200.

The previous prime is 687647315995891. The next prime is 687647315995963. The reversal of 687647315995920 is 29599513746786.

687647315995920 is a `hidden beast` number, since 6 + 8 + 7 + 6 + 4 + 7 + 3 + 15 + 9 + 9 + 592 + 0 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 687647315995920.

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 255 ways as a sum of consecutive naturals, for example, 79579594800 + ... + 79579603440.

It is an arithmetic number, because the mean of its divisors is an integer number (2181348099072).

It is a 2-persistent number, because it is pandigital, and so is 2⋅687647315995920 = 1375294631991840, but 3⋅687647315995920 = 2062941947987760 is not.

Almost surely, 2^{687647315995920} is an apocalyptic number.

687647315995920 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 687647315995920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1396062783406080).

687647315995920 is an abundant number, since it is smaller than the sum of its proper divisors (2104478250816240).

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

687647315995920 is a wasteful number, since it uses less digits than its factorization.

687647315995920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9821 (or 9809 counting only the distinct ones).

The product of its (nonzero) digits is 6172588800, while the sum is 81.

The spelling of 687647315995920 in words is "six hundred eighty-seven trillion, six hundred forty-seven billion, three hundred fifteen million, nine hundred ninety-five thousand, nine hundred twenty".