68288721 has 8 divisors (see below), whose sum is σ = 92075040. Its totient is φ = 45014112.

The previous prime is 68288719. The next prime is 68288729. The reversal of 68288721 is 12788286.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 68288721 - 2¹ = 68288719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (68288729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 127615 + ... + 128148.

It is an arithmetic number, because the mean of its divisors is an integer number (11509380).

Almost surely, 2^68288721 is an apocalyptic number.

It is an amenable number.

68288721 is a deficient number, since it is larger than the sum of its proper divisors (23786319).

68288721 is a wasteful number, since it uses less digits than its factorization.

68288721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255855.

The product of its digits is 86016, while the sum is 42.

The square root of 68288721 is about 8263.6989901617. The cubic root of 68288721 is about 408.7423707766.

The spelling of 68288721 in words is "sixty-eight million, two hundred eighty-eight thousand, seven hundred twenty-one".