66111251605617 has 8 divisors (see below), whose sum is σ = 88148432042496. Its totient is φ = 44074119452912.

The previous prime is 66111251605601. The next prime is 66111251605643. The reversal of 66111251605617 is 71650615211166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66111251605617 - 2⁴ = 66111251605601 is a prime.

It is a super-2 number, since 2×66111251605617² (a number of 28 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66111251605687) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8745318 + ... + 14446559.

It is an arithmetic number, because the mean of its divisors is an integer number (11018554005312).

Almost surely, 2^{66111251605617} is an apocalyptic number.

It is an amenable number.

66111251605617 is a deficient number, since it is larger than the sum of its proper divisors (22037180436879).

66111251605617 is a wasteful number, since it uses less digits than its factorization.

66111251605617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24142087.

The product of its (nonzero) digits is 453600, while the sum is 48.

The spelling of 66111251605617 in words is "sixty-six trillion, one hundred eleven billion, two hundred fifty-one million, six hundred five thousand, six hundred seventeen".