68293781 has 2 divisors, whose sum is σ = 68293782. Its totient is φ = 68293780.

The previous prime is 68293751. The next prime is 68293789. The reversal of 68293781 is 18739286.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45778756 + 22515025 = 6766^2 + 4745^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68293781 is a prime.

It is a super-2 number, since 2×68293781² = 9328081046551922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68293789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34146890 + 34146891.

It is an arithmetic number, because the mean of its divisors is an integer number (34146891).

Almost surely, 2^68293781 is an apocalyptic number.

It is an amenable number.

68293781 is a deficient number, since it is larger than the sum of its proper divisors (1).

68293781 is an equidigital number, since it uses as much as digits as its factorization.

68293781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145152, while the sum is 44.

The square root of 68293781 is about 8264.0051427864. The cubic root of 68293781 is about 408.7524660763.

The spelling of 68293781 in words is "sixty-eight million, two hundred ninety-three thousand, seven hundred eighty-one".