16611665997 has 8 divisors (see below), whose sum is σ = 22165584256. Its totient is φ = 11066095872.

The previous prime is 16611665989. The next prime is 16611666007. The reversal of 16611665997 is 79956611661.

It is a happy number.

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

It is not a de Polignac number, because 16611665997 - 2³ = 16611665989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16611665977) 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, 2082388 + ... + 2090349.

It is an arithmetic number, because the mean of its divisors is an integer number (2770698032).

Almost surely, 2^16611665997 is an apocalyptic number.

It is an amenable number.

16611665997 is a deficient number, since it is larger than the sum of its proper divisors (5553918259).

16611665997 is a wasteful number, since it uses less digits than its factorization.

16611665997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4174067.

The product of its digits is 3674160, while the sum is 57.

The spelling of 16611665997 in words is "sixteen billion, six hundred eleven million, six hundred sixty-five thousand, nine hundred ninety-seven".