16788290665 has 4 divisors (see below), whose sum is σ = 20145948804. Its totient is φ = 13430632528.

The previous prime is 16788290657. The next prime is 16788290669. The reversal of 16788290665 is 56609288761.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56609288761 = 193 ⋅293312377.

It can be written as a sum of positive squares in 2 ways, for example, as 4591959696 + 12196330969 = 67764^2 + 110437^2 .

It is a cyclic number.

It is not a de Polignac number, because 16788290665 - 2³ = 16788290657 is a prime.

It is a super-2 number, since 2×16788290665² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16788290669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1678829062 + ... + 1678829071.

It is an arithmetic number, because the mean of its divisors is an integer number (5036487201).

Almost surely, 2^16788290665 is an apocalyptic number.

It is an amenable number.

16788290665 is a deficient number, since it is larger than the sum of its proper divisors (3357658139).

16788290665 is an equidigital number, since it uses as much as digits as its factorization.

16788290665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3357658138.

The product of its (nonzero) digits is 8709120, while the sum is 58.

The spelling of 16788290665 in words is "sixteen billion, seven hundred eighty-eight million, two hundred ninety thousand, six hundred sixty-five".