66611109501 has 24 divisors (see below), whose sum is σ = 96411332160. Its totient is φ = 44317371456.

The previous prime is 66611109491. The next prime is 66611109517. The reversal of 66611109501 is 10590111666.

It is not a de Polignac number, because 66611109501 - 2⁹ = 66611108989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66611119501) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11843376 + ... + 11848998.

It is an arithmetic number, because the mean of its divisors is an integer number (4017138840).

Almost surely, 2^66611109501 is an apocalyptic number.

It is an amenable number.

66611109501 is a deficient number, since it is larger than the sum of its proper divisors (29800222659).

66611109501 is a wasteful number, since it uses less digits than its factorization.

66611109501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8065 (or 8062 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

The spelling of 66611109501 in words is "sixty-six billion, six hundred eleven million, one hundred nine thousand, five hundred one".