68318640 has 200 divisors, whose sum is σ = 255848208. Its totient is φ = 16796160.

The previous prime is 68318611. The next prime is 68318641. The reversal of 68318640 is 4681386.

It is a happy number.

68318640 is a `hidden beast` number, since 6 + 8 + 3 + 1 + 8 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 68318595 and 68318604.

It is not an unprimeable number, because it can be changed into a prime (68318641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 83835 + ... + 84645.

Almost surely, 2^68318640 is an apocalyptic number.

68318640 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 68318640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127924104).

68318640 is an abundant number, since it is smaller than the sum of its proper divisors (187529568).

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

68318640 is a wasteful number, since it uses less digits than its factorization.

68318640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 849 (or 834 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 68318640 is about 8265.5090587332. The cubic root of 68318640 is about 408.8020554863.

The spelling of 68318640 in words is "sixty-eight million, three hundred eighteen thousand, six hundred forty".