66971719511 has 2 divisors, whose sum is σ = 66971719512. Its totient is φ = 66971719510.

The previous prime is 66971719483. The next prime is 66971719537. The reversal of 66971719511 is 11591717966.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66971719511 - 2¹⁸ = 66971457367 is a prime.

It is a super-2 number, since 2×66971719511² (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 (66971719571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33485859755 + 33485859756.

It is an arithmetic number, because the mean of its divisors is an integer number (33485859756).

Almost surely, 2^66971719511 is an apocalyptic number.

66971719511 is a deficient number, since it is larger than the sum of its proper divisors (1).

66971719511 is an equidigital number, since it uses as much as digits as its factorization.

66971719511 is an evil number, because the sum of its binary digits is even.

The product of its digits is 714420, while the sum is 53.

The spelling of 66971719511 in words is "sixty-six billion, nine hundred seventy-one million, seven hundred nineteen thousand, five hundred eleven".