16651542665 has 16 divisors (see below), whose sum is σ = 20250259200. Its totient is φ = 13142946432.

The previous prime is 16651542637. The next prime is 16651542671. The reversal of 16651542665 is 56624515661.

It is a cyclic number.

It is not a de Polignac number, because 16651542665 - 2⁸ = 16651542409 is a prime.

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, 165626 + ... + 246444.

It is an arithmetic number, because the mean of its divisors is an integer number (1265641200).

Almost surely, 2^16651542665 is an apocalyptic number.

It is an amenable number.

16651542665 is a deficient number, since it is larger than the sum of its proper divisors (3598716535).

16651542665 is an equidigital number, since it uses as much as digits as its factorization.

16651542665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81376.

The product of its digits is 1296000, while the sum is 47.

The spelling of 16651542665 in words is "sixteen billion, six hundred fifty-one million, five hundred forty-two thousand, six hundred sixty-five".