66443540237 has 2 divisors, whose sum is σ = 66443540238. Its totient is φ = 66443540236.

The previous prime is 66443540161. The next prime is 66443540239. The reversal of 66443540237 is 73204534466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54652620841 + 11790919396 = 233779^2 + 108586^2 .

It is a cyclic number.

It is not a de Polignac number, because 66443540237 - 2¹² = 66443536141 is a prime.

Together with 66443540239, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66443540239) 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, 33221770118 + 33221770119.

It is an arithmetic number, because the mean of its divisors is an integer number (33221770119).

Almost surely, 2^66443540237 is an apocalyptic number.

It is an amenable number.

66443540237 is a deficient number, since it is larger than the sum of its proper divisors (1).

66443540237 is an equidigital number, since it uses as much as digits as its factorization.

66443540237 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1451520, while the sum is 44.

The spelling of 66443540237 in words is "sixty-six billion, four hundred forty-three million, five hundred forty thousand, two hundred thirty-seven".