66065999957 has 2 divisors, whose sum is σ = 66065999958. Its totient is φ = 66065999956.

The previous prime is 66065999921. The next prime is 66066000031. The reversal of 66065999957 is 75999956066.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45368574001 + 20697425956 = 212999^2 + 143866^2 .

It is a cyclic number.

It is not a de Polignac number, because 66065999957 - 2¹⁶ = 66065934421 is a prime.

It is a super-4 number, since 4×66065999957⁴ (a number of 44 digits) contains 4444 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66065999057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33032999978 + 33032999979.

It is an arithmetic number, because the mean of its divisors is an integer number (33032999979).

Almost surely, 2^66065999957 is an apocalyptic number.

It is an amenable number.

66065999957 is a deficient number, since it is larger than the sum of its proper divisors (1).

66065999957 is an equidigital number, since it uses as much as digits as its factorization.

66065999957 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 248005800, while the sum is 71.

The spelling of 66065999957 in words is "sixty-six billion, sixty-five million, nine hundred ninety-nine thousand, nine hundred fifty-seven".