68391539 has 2 divisors, whose sum is σ = 68391540. Its totient is φ = 68391538.

The previous prime is 68391529. The next prime is 68391601. The reversal of 68391539 is 93519386.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68391539 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 68391539.

It is not a weakly prime, because it can be changed into another prime (68391509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34195769 + 34195770.

It is an arithmetic number, because the mean of its divisors is an integer number (34195770).

Almost surely, 2^68391539 is an apocalyptic number.

68391539 is a deficient number, since it is larger than the sum of its proper divisors (1).

68391539 is an equidigital number, since it uses as much as digits as its factorization.

68391539 is an evil number, because the sum of its binary digits is even.

The product of its digits is 174960, while the sum is 44.

The square root of 68391539 is about 8269.9177142218. The cubic root of 68391539 is about 408.9474070700.

The spelling of 68391539 in words is "sixty-eight million, three hundred ninety-one thousand, five hundred thirty-nine".