68409917 has 2 divisors, whose sum is σ = 68409918. Its totient is φ = 68409916.

The previous prime is 68409911. The next prime is 68409931. The reversal of 68409917 is 71990486.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34234201 + 34175716 = 5851^2 + 5846^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68409917 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68409911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34204958 + 34204959.

It is an arithmetic number, because the mean of its divisors is an integer number (34204959).

Almost surely, 2^68409917 is an apocalyptic number.

It is an amenable number.

68409917 is a deficient number, since it is larger than the sum of its proper divisors (1).

68409917 is an equidigital number, since it uses as much as digits as its factorization.

68409917 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 44.

The square root of 68409917 is about 8271.0287751887. The cubic root of 68409917 is about 408.9840342243.

The spelling of 68409917 in words is "sixty-eight million, four hundred nine thousand, nine hundred seventeen".