67817801856 has 128 divisors (see below), whose sum is σ = 205961500800. Its totient is φ = 19368419328.

The previous prime is 67817801819. The next prime is 67817801879. The reversal of 67817801856 is 65810871876.

It is a tau number, because it is divible by the number of its divisors (128).

It is a junction number, because it is equal to n+sod(n) for n = 67817801796 and 67817801805.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9869590 + ... + 9876458.

It is an arithmetic number, because the mean of its divisors is an integer number (1609074225).

Almost surely, 2^67817801856 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 67817801856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102980750400).

67817801856 is an abundant number, since it is smaller than the sum of its proper divisors (138143698944).

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

67817801856 is a wasteful number, since it uses less digits than its factorization.

67817801856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10566 (or 10554 counting only the distinct ones).

The product of its (nonzero) digits is 4515840, while the sum is 57.

The spelling of 67817801856 in words is "sixty-seven billion, eight hundred seventeen million, eight hundred one thousand, eight hundred fifty-six".