16651155665 has 16 divisors (see below), whose sum is σ = 21503601360. Its totient is φ = 12331806720.

The previous prime is 16651155659. The next prime is 16651155691. The reversal of 16651155665 is 56655115661.

It can be written as a sum of positive squares in 8 ways, for example, as 227195329 + 16423960336 = 15073^2 + 128156^2 .

It is not a de Polignac number, because 16651155665 - 2²² = 16646961361 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1600520 + ... + 1610889.

It is an arithmetic number, because the mean of its divisors is an integer number (1343975085).

Almost surely, 2^16651155665 is an apocalyptic number.

It is an amenable number.

16651155665 is a deficient number, since it is larger than the sum of its proper divisors (4852445695).

16651155665 is a wasteful number, since it uses less digits than its factorization.

16651155665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3211492.

The product of its digits is 810000, while the sum is 47.

The spelling of 16651155665 in words is "sixteen billion, six hundred fifty-one million, one hundred fifty-five thousand, six hundred sixty-five".