68781917 has 2 divisors, whose sum is σ = 68781918. Its totient is φ = 68781916.

The previous prime is 68781907. The next prime is 68781941. The reversal of 68781917 is 71918786.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 36132121 + 32649796 = 6011^2 + 5714^2 .

It is a cyclic number.

It is not a de Polignac number, because 68781917 - 2¹⁶ = 68716381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68781907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34390958 + 34390959.

It is an arithmetic number, because the mean of its divisors is an integer number (34390959).

Almost surely, 2^68781917 is an apocalyptic number.

It is an amenable number.

68781917 is a deficient number, since it is larger than the sum of its proper divisors (1).

68781917 is an equidigital number, since it uses as much as digits as its factorization.

68781917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 169344, while the sum is 47.

The square root of 68781917 is about 8293.4864200769. The cubic root of 68781917 is about 409.7240201035.

The spelling of 68781917 in words is "sixty-eight million, seven hundred eighty-one thousand, nine hundred seventeen".