16812656689 has 4 divisors (see below), whose sum is σ = 16817734756. Its totient is φ = 16807578624.

The previous prime is 16812656687. The next prime is 16812656717. The reversal of 16812656689 is 98665621861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98665621861 = 13613 ⋅7247897.

It can be written as a sum of positive squares in 2 ways, for example, as 16360456464 + 452200225 = 127908^2 + 21265^2 .

It is a cyclic number.

It is not a de Polignac number, because 16812656689 - 2¹ = 16812656687 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16812656687) 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, 2534064 + ... + 2540689.

It is an arithmetic number, because the mean of its divisors is an integer number (4204433689).

Almost surely, 2^16812656689 is an apocalyptic number.

It is an amenable number.

16812656689 is a deficient number, since it is larger than the sum of its proper divisors (5078067).

16812656689 is an equidigital number, since it uses as much as digits as its factorization.

16812656689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5078066.

The product of its digits is 7464960, while the sum is 58.

The spelling of 16812656689 in words is "sixteen billion, eight hundred twelve million, six hundred fifty-six thousand, six hundred eighty-nine".