66661111611 has 24 divisors (see below), whose sum is σ = 99227497824. Its totient is φ = 43097159040.

The previous prime is 66661111597. The next prime is 66661111633. The reversal of 66661111611 is 11611116666.

It is not a de Polignac number, because 66661111611 - 2¹³ = 66661103419 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66661111411) 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 in 23 ways as a sum of consecutive naturals, for example, 479256 + ... + 602501.

It is an arithmetic number, because the mean of its divisors is an integer number (4134479076).

Almost surely, 2^66661111611 is an apocalyptic number.

66661111611 is a deficient number, since it is larger than the sum of its proper divisors (32566386213).

66661111611 is a wasteful number, since it uses less digits than its factorization.

66661111611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1081971 (or 1081968 counting only the distinct ones).

The product of its digits is 7776, while the sum is 36.

The spelling of 66661111611 in words is "sixty-six billion, six hundred sixty-one million, one hundred eleven thousand, six hundred eleven".