68929840 has 80 divisors (see below), whose sum is σ = 185488128. Its totient is φ = 23332608.

The previous prime is 68929829. The next prime is 68929843. The reversal of 68929840 is 4892986.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (68929843) 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 15 ways as a sum of consecutive naturals, for example, 45739 + ... + 47221.

Almost surely, 2^68929840 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 68929840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92744064).

68929840 is an abundant number, since it is smaller than the sum of its proper divisors (116558288).

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

68929840 is a wasteful number, since it uses less digits than its factorization.

68929840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1586 (or 1580 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 46.

The square root of 68929840 is about 8302.3996531123. The cubic root of 68929840 is about 410.0175284991.

The spelling of 68929840 in words is "sixty-eight million, nine hundred twenty-nine thousand, eight hundred forty".