66344265433981 has 2 divisors, whose sum is σ = 66344265433982. Its totient is φ = 66344265433980.

The previous prime is 66344265433961. The next prime is 66344265433987. The reversal of 66344265433981 is 18933456244366.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59453876681956 + 6890388752025 = 7710634^2 + 2624955^2 .

It is a cyclic number.

It is not a de Polignac number, because 66344265433981 - 2²¹ = 66344263336829 is a prime.

It is a super-2 number, since 2×66344265433981² (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 (66344265433987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33172132716990 + 33172132716991.

It is an arithmetic number, because the mean of its divisors is an integer number (33172132716991).

Almost surely, 2^{66344265433981} is an apocalyptic number.

It is an amenable number.

66344265433981 is a deficient number, since it is larger than the sum of its proper divisors (1).

66344265433981 is an equidigital number, since it uses as much as digits as its factorization.

66344265433981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 268738560, while the sum is 64.

The spelling of 66344265433981 in words is "sixty-six trillion, three hundred forty-four billion, two hundred sixty-five million, four hundred thirty-three thousand, nine hundred eighty-one".