66691212577611 has 16 divisors (see below), whose sum is σ = 92815153447680. Its totient is φ = 42515180855840.

The previous prime is 66691212577609. The next prime is 66691212577621. The reversal of 66691212577611 is 11677521219666.

It is a cyclic number.

It is not a de Polignac number, because 66691212577611 - 2¹ = 66691212577609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66691212577621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 142365645 + ... + 142833326.

It is an arithmetic number, because the mean of its divisors is an integer number (5800947090480).

Almost surely, 2^{66691212577611} is an apocalyptic number.

66691212577611 is a deficient number, since it is larger than the sum of its proper divisors (26123940870069).

66691212577611 is a wasteful number, since it uses less digits than its factorization.

66691212577611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285202386.

The product of its digits is 11430720, while the sum is 60.

The spelling of 66691212577611 in words is "sixty-six trillion, six hundred ninety-one billion, two hundred twelve million, five hundred seventy-seven thousand, six hundred eleven".