66673666733381 has 2 divisors, whose sum is σ = 66673666733382. Its totient is φ = 66673666733380.

The previous prime is 66673666733351. The next prime is 66673666733423. The reversal of 66673666733381 is 18333766637666.

66673666733381 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51741694648900 + 14931972084481 = 7193170^2 + 3864191^2 .

It is a cyclic number.

It is not a de Polignac number, because 66673666733381 - 2¹⁴ = 66673666716997 is a prime.

It is a super-2 number, since 2×66673666733381² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66673666733351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33336833366690 + 33336833366691.

It is an arithmetic number, because the mean of its divisors is an integer number (33336833366691).

Almost surely, 2^{66673666733381} is an apocalyptic number.

It is an amenable number.

66673666733381 is a deficient number, since it is larger than the sum of its proper divisors (1).

66673666733381 is an equidigital number, since it uses as much as digits as its factorization.

66673666733381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1481421312, while the sum is 71.

The spelling of 66673666733381 in words is "sixty-six trillion, six hundred seventy-three billion, six hundred sixty-six million, seven hundred thirty-three thousand, three hundred eighty-one".