11665201666 has 8 divisors (see below), whose sum is σ = 17524848960. Its totient is φ = 5823585348.

The previous prime is 11665201643. The next prime is 11665201673. The reversal of 11665201666 is 66610256611.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4506126 + ... + 4508713.

It is an arithmetic number, because the mean of its divisors is an integer number (2190606120).

Almost surely, 2^11665201666 is an apocalyptic number.

11665201666 is a deficient number, since it is larger than the sum of its proper divisors (5859647294).

11665201666 is an equidigital number, since it uses as much as digits as its factorization.

11665201666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9015488.

The product of its (nonzero) digits is 77760, while the sum is 40.

Subtracting 11665201666 from its reverse (66610256611), we obtain a palindrome (54945054945).

The spelling of 11665201666 in words is "eleven billion, six hundred sixty-five million, two hundred one thousand, six hundred sixty-six".