16306386661 has 4 divisors (see below), whose sum is σ = 16747099852. Its totient is φ = 15865673472.

The previous prime is 16306386647. The next prime is 16306386667. The reversal of 16306386661 is 16668360361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16668360361 = 241 ⋅69163321.

It can be written as a sum of positive squares in 2 ways, for example, as 13177662436 + 3128724225 = 114794^2 + 55935^2 .

It is a cyclic number.

It is not a de Polignac number, because 16306386661 - 2⁹ = 16306386149 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 (16306386667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 220356540 + ... + 220356613.

It is an arithmetic number, because the mean of its divisors is an integer number (4186774963).

Almost surely, 2^16306386661 is an apocalyptic number.

It is an amenable number.

16306386661 is a deficient number, since it is larger than the sum of its proper divisors (440713191).

16306386661 is an equidigital number, since it uses as much as digits as its factorization.

16306386661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440713190.

The product of its (nonzero) digits is 559872, while the sum is 46.

The spelling of 16306386661 in words is "sixteen billion, three hundred six million, three hundred eighty-six thousand, six hundred sixty-one".