66505756507 has 2 divisors, whose sum is σ = 66505756508. Its totient is φ = 66505756506.

The previous prime is 66505756441. The next prime is 66505756529. The reversal of 66505756507 is 70565750566.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66505756507 - 2¹⁹ = 66505232219 is a prime.

It is not a weakly prime, because it can be changed into another prime (66505706507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33252878253 + 33252878254.

It is an arithmetic number, because the mean of its divisors is an integer number (33252878254).

Almost surely, 2^66505756507 is an apocalyptic number.

66505756507 is a deficient number, since it is larger than the sum of its proper divisors (1).

66505756507 is an equidigital number, since it uses as much as digits as its factorization.

66505756507 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6615000, while the sum is 52.

The spelling of 66505756507 in words is "sixty-six billion, five hundred five million, seven hundred fifty-six thousand, five hundred seven".