66511567651 has 2 divisors, whose sum is σ = 66511567652. Its totient is φ = 66511567650.

The previous prime is 66511567643. The next prime is 66511567691. The reversal of 66511567651 is 15676511566.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66511567651 - 2³ = 66511567643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66511567595 and 66511567604.

It is not a weakly prime, because it can be changed into another prime (66511567631) 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, 33255783825 + 33255783826.

It is an arithmetic number, because the mean of its divisors is an integer number (33255783826).

Almost surely, 2^66511567651 is an apocalyptic number.

66511567651 is a deficient number, since it is larger than the sum of its proper divisors (1).

66511567651 is an equidigital number, since it uses as much as digits as its factorization.

66511567651 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1134000, while the sum is 49.

The spelling of 66511567651 in words is "sixty-six billion, five hundred eleven million, five hundred sixty-seven thousand, six hundred fifty-one".