68407993 has 2 divisors, whose sum is σ = 68407994. Its totient is φ = 68407992.

The previous prime is 68407939. The next prime is 68408033. The reversal of 68407993 is 39970486.

Together with previous prime (68407939) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65157184 + 3250809 = 8072^2 + 1803^2 .

It is a cyclic number.

It is not a de Polignac number, because 68407993 - 2⁹ = 68407481 is a prime.

It is not a weakly prime, because it can be changed into another prime (68407903) 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, 34203996 + 34203997.

It is an arithmetic number, because the mean of its divisors is an integer number (34203997).

Almost surely, 2^68407993 is an apocalyptic number.

It is an amenable number.

68407993 is a deficient number, since it is larger than the sum of its proper divisors (1).

68407993 is an equidigital number, since it uses as much as digits as its factorization.

68407993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 326592, while the sum is 46.

The square root of 68407993 is about 8270.9124647768. The cubic root of 68407993 is about 408.9802000207.

The spelling of 68407993 in words is "sixty-eight million, four hundred seven thousand, nine hundred ninety-three".