68186721 has 16 divisors (see below), whose sum is σ = 92476800. Its totient is φ = 44684160.

The previous prime is 68186719. The next prime is 68186759. The reversal of 68186721 is 12768186.

It is not a de Polignac number, because 68186721 - 2¹ = 68186719 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 68186721.

It is not an unprimeable number, because it can be changed into a prime (68186621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45301 + ... + 46781.

It is an arithmetic number, because the mean of its divisors is an integer number (5779800).

Almost surely, 2^68186721 is an apocalyptic number.

It is an amenable number.

68186721 is a deficient number, since it is larger than the sum of its proper divisors (24290079).

68186721 is a wasteful number, since it uses less digits than its factorization.

68186721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1736.

The product of its digits is 32256, while the sum is 39.

The square root of 68186721 is about 8257.5251134950. The cubic root of 68186721 is about 408.5387622540.

The spelling of 68186721 in words is "sixty-eight million, one hundred eighty-six thousand, seven hundred twenty-one".