67665554321 has 2 divisors, whose sum is σ = 67665554322. Its totient is φ = 67665554320.

The previous prime is 67665554267. The next prime is 67665554357. The reversal of 67665554321 is 12345556676.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64691379025 + 2974175296 = 254345^2 + 54536^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-67665554321 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 67665554321.

It is not a weakly prime, because it can be changed into another prime (67665554371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33832777160 + 33832777161.

It is an arithmetic number, because the mean of its divisors is an integer number (33832777161).

Almost surely, 2^67665554321 is an apocalyptic number.

It is an amenable number.

67665554321 is a deficient number, since it is larger than the sum of its proper divisors (1).

67665554321 is an equidigital number, since it uses as much as digits as its factorization.

67665554321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4536000, while the sum is 50.

The spelling of 67665554321 in words is "sixty-seven billion, six hundred sixty-five million, five hundred fifty-four thousand, three hundred twenty-one".