67389978656 has 576 divisors, whose sum is σ = 192726003456. Its totient is φ = 22383820800.

The previous prime is 67389978553. The next prime is 67389978713. The reversal of 67389978656 is 65687998376.

It is a super-2 number, since 2×67389978656² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 694742000 + ... + 694742096.

It is an arithmetic number, because the mean of its divisors is an integer number (334593756).

Almost surely, 2^67389978656 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 67389978656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96363001728).

67389978656 is an abundant number, since it is smaller than the sum of its proper divisors (125336024800).

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

67389978656 is a wasteful number, since it uses less digits than its factorization.

67389978656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225 (or 194 counting only the distinct ones).

The product of its digits is 823011840, while the sum is 74.

The spelling of 67389978656 in words is "sixty-seven billion, three hundred eighty-nine million, nine hundred seventy-eight thousand, six hundred fifty-six".