16051566651665 has 8 divisors (see below), whose sum is σ = 19311396385320. Its totient is φ = 12808242385792.

The previous prime is 16051566651643. The next prime is 16051566651667. The reversal of 16051566651665 is 56615666515061.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 29543078161 + 16022023573504 = 171881^2 + 4002752^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 16051566651665 - 2²⁶ = 16051499542801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16051566651667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4126364804 + ... + 4126368693.

It is an arithmetic number, because the mean of its divisors is an integer number (2413924548165).

Almost surely, 2^{16051566651665} is an apocalyptic number.

It is an amenable number.

16051566651665 is a deficient number, since it is larger than the sum of its proper divisors (3259829733655).

16051566651665 is an equidigital number, since it uses as much as digits as its factorization.

16051566651665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8252733891.

The product of its (nonzero) digits is 29160000, while the sum is 59.

The spelling of 16051566651665 in words is "sixteen trillion, fifty-one billion, five hundred sixty-six million, six hundred fifty-one thousand, six hundred sixty-five".