66630905251 has 2 divisors, whose sum is σ = 66630905252. Its totient is φ = 66630905250.

The previous prime is 66630905239. The next prime is 66630905261. The reversal of 66630905251 is 15250903666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66630905251 - 2¹⁷ = 66630774179 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66630905198 and 66630905207.

It is not a weakly prime, because it can be changed into another prime (66630905261) 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, 33315452625 + 33315452626.

It is an arithmetic number, because the mean of its divisors is an integer number (33315452626).

Almost surely, 2^66630905251 is an apocalyptic number.

66630905251 is a deficient number, since it is larger than the sum of its proper divisors (1).

66630905251 is an equidigital number, since it uses as much as digits as its factorization.

66630905251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 291600, while the sum is 43.

The spelling of 66630905251 in words is "sixty-six billion, six hundred thirty million, nine hundred five thousand, two hundred fifty-one".