66201623869 has 2 divisors, whose sum is σ = 66201623870. Its totient is φ = 66201623868.

The previous prime is 66201623783. The next prime is 66201623959. The reversal of 66201623869 is 96832610266.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48691718244 + 17509905625 = 220662^2 + 132325^2 .

It is a cyclic number.

It is not a de Polignac number, because 66201623869 - 2¹³ = 66201615677 is a prime.

It is a super-2 number, since 2×66201623869² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66201624869) 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, 33100811934 + 33100811935.

It is an arithmetic number, because the mean of its divisors is an integer number (33100811935).

Almost surely, 2^66201623869 is an apocalyptic number.

It is an amenable number.

66201623869 is a deficient number, since it is larger than the sum of its proper divisors (1).

66201623869 is an equidigital number, since it uses as much as digits as its factorization.

66201623869 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1119744, while the sum is 49.

The spelling of 66201623869 in words is "sixty-six billion, two hundred one million, six hundred twenty-three thousand, eight hundred sixty-nine".