16566665665 has 32 divisors (see below), whose sum is σ = 22977302400. Its totient is φ = 11332684800.

The previous prime is 16566665627. The next prime is 16566665669. The reversal of 16566665665 is 56656666561.

It is not a de Polignac number, because 16566665665 - 2¹⁹ = 16566141377 is a prime.

It is a super-3 number, since 3×16566665665³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (16566665669) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1817770 + ... + 1826860.

It is an arithmetic number, because the mean of its divisors is an integer number (718040700).

Almost surely, 2^16566665665 is an apocalyptic number.

It is an amenable number.

16566665665 is a deficient number, since it is larger than the sum of its proper divisors (6410636735).

16566665665 is a wasteful number, since it uses less digits than its factorization.

16566665665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11073.

The product of its digits is 34992000, while the sum is 58.

The spelling of 16566665665 in words is "sixteen billion, five hundred sixty-six million, six hundred sixty-five thousand, six hundred sixty-five".