15516551166161 has 4 divisors (see below), whose sum is σ = 15516586377012. Its totient is φ = 15516515955312.

The previous prime is 15516551166143. The next prime is 15516551166187. The reversal of 15516551166161 is 16166115561551.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15407634665536 + 108916500625 = 3925256^2 + 330025^2 .

It is a cyclic number.

It is not a de Polignac number, because 15516551166161 - 2⁶ = 15516551166097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15516551196161) 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, 16935926 + ... + 17828591.

It is an arithmetic number, because the mean of its divisors is an integer number (3879146594253).

Almost surely, 2^{15516551166161} is an apocalyptic number.

It is an amenable number.

15516551166161 is a deficient number, since it is larger than the sum of its proper divisors (35210851).

15516551166161 is an equidigital number, since it uses as much as digits as its factorization.

15516551166161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35210850.

The product of its digits is 810000, while the sum is 50.

The spelling of 15516551166161 in words is "fifteen trillion, five hundred sixteen billion, five hundred fifty-one million, one hundred sixty-six thousand, one hundred sixty-one".