68195721 has 48 divisors (see below), whose sum is σ = 108706752. Its totient is φ = 37847040.

The previous prime is 68195711. The next prime is 68195747. The reversal of 68195721 is 12759186.

It is not a de Polignac number, because 68195721 - 2¹¹ = 68193673 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 68195721.

It is not an unprimeable number, because it can be changed into a prime (68195711) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 265225 + ... + 265481.

It is an arithmetic number, because the mean of its divisors is an integer number (2264724).

Almost surely, 2^68195721 is an apocalyptic number.

It is an amenable number.

68195721 is a deficient number, since it is larger than the sum of its proper divisors (40511031).

68195721 is a wasteful number, since it uses less digits than its factorization.

68195721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342 (or 331 counting only the distinct ones).

The product of its digits is 30240, while the sum is 39.

The square root of 68195721 is about 8258.0700529845. The cubic root of 68195721 is about 408.5567358763.

The spelling of 68195721 in words is "sixty-eight million, one hundred ninety-five thousand, seven hundred twenty-one".