16651166651 has 4 divisors (see below), whose sum is σ = 19029904752. Its totient is φ = 14272428552.

The previous prime is 16651166603. The next prime is 16651166659. The reversal of 16651166651 is 15666115661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15666115661 = 7 ⋅2238016523.

It is a cyclic number.

It is not a de Polignac number, because 16651166651 - 2¹⁴ = 16651150267 is a prime.

It is a super-2 number, since 2×16651166651² (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 (16651166659) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1189369040 + ... + 1189369053.

It is an arithmetic number, because the mean of its divisors is an integer number (4757476188).

Almost surely, 2^16651166651 is an apocalyptic number.

16651166651 is a deficient number, since it is larger than the sum of its proper divisors (2378738101).

16651166651 is an equidigital number, since it uses as much as digits as its factorization.

16651166651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2378738100.

The product of its digits is 194400, while the sum is 44.

The spelling of 16651166651 in words is "sixteen billion, six hundred fifty-one million, one hundred sixty-six thousand, six hundred fifty-one".