66995344457 has 2 divisors, whose sum is σ = 66995344458. Its totient is φ = 66995344456.

The previous prime is 66995344447. The next prime is 66995344463. The reversal of 66995344457 is 75444359966.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66927759616 + 67584841 = 258704^2 + 8221^2 .

It is a cyclic number.

It is not a de Polignac number, because 66995344457 - 2¹² = 66995340361 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66995344457.

It is not a weakly prime, because it can be changed into another prime (66995344417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33497672228 + 33497672229.

It is an arithmetic number, because the mean of its divisors is an integer number (33497672229).

Almost surely, 2^66995344457 is an apocalyptic number.

It is an amenable number.

66995344457 is a deficient number, since it is larger than the sum of its proper divisors (1).

66995344457 is an equidigital number, since it uses as much as digits as its factorization.

66995344457 is an evil number, because the sum of its binary digits is even.

The product of its digits is 97977600, while the sum is 62.

The spelling of 66995344457 in words is "sixty-six billion, nine hundred ninety-five million, three hundred forty-four thousand, four hundred fifty-seven".