68359721 has 2 divisors, whose sum is σ = 68359722. Its totient is φ = 68359720.

The previous prime is 68359693. The next prime is 68359747. The reversal of 68359721 is 12795386.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68244121 + 115600 = 8261^2 + 340^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68359721 is a prime.

It is not a weakly prime, because it can be changed into another prime (68359021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34179860 + 34179861.

It is an arithmetic number, because the mean of its divisors is an integer number (34179861).

Almost surely, 2^68359721 is an apocalyptic number.

It is an amenable number.

68359721 is a deficient number, since it is larger than the sum of its proper divisors (1).

68359721 is an equidigital number, since it uses as much as digits as its factorization.

68359721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 41.

The square root of 68359721 is about 8267.9937711636. The cubic root of 68359721 is about 408.8839786247.

The spelling of 68359721 in words is "sixty-eight million, three hundred fifty-nine thousand, seven hundred twenty-one".