1166172161 has 16 divisors (see below), whose sum is σ = 1471454208. Its totient is φ = 897752400.

The previous prime is 1166172127. The next prime is 1166172181. The reversal of 1166172161 is 1612716611.

It is a cyclic number.

It is not a de Polignac number, because 1166172161 - 2¹⁸ = 1165910017 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1166172181) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 84845 + ... + 97626.

It is an arithmetic number, because the mean of its divisors is an integer number (91965888).

Almost surely, 2^1166172161 is an apocalyptic number.

1166172161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1166172161 is a deficient number, since it is larger than the sum of its proper divisors (305282047).

1166172161 is a wasteful number, since it uses less digits than its factorization.

1166172161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182572.

The product of its digits is 3024, while the sum is 32.

The square root of 1166172161 is about 34149.2629642281. The cubic root of 1166172161 is about 1052.5778416558.

Adding to 1166172161 its reverse (1612716611), we get a palindrome (2778888772).

The spelling of 1166172161 in words is "one billion, one hundred sixty-six million, one hundred seventy-two thousand, one hundred sixty-one".