68404688 has 60 divisors (see below), whose sum is σ = 147685860. Its totient is φ = 30666240.

The previous prime is 68404681. The next prime is 68404711. The reversal of 68404688 is 88640486.

It can be written as a sum of positive squares in 2 ways, for example, as 28815424 + 39589264 = 5368^2 + 6292^2 .

It is a super-3 number, since 3×68404688³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68404681) 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 11 ways as a sum of consecutive naturals, for example, 172106 + ... + 172502.

It is an arithmetic number, because the mean of its divisors is an integer number (2461431).

Almost surely, 2^68404688 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 68404688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73842930).

68404688 is an abundant number, since it is smaller than the sum of its proper divisors (79281172).

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

68404688 is a wasteful number, since it uses less digits than its factorization.

68404688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 516 (or 499 counting only the distinct ones).

The product of its (nonzero) digits is 294912, while the sum is 44.

The square root of 68404688 is about 8270.7126657864. The cubic root of 68404688 is about 408.9736135519.

The spelling of 68404688 in words is "sixty-eight million, four hundred four thousand, six hundred eighty-eight".