12186172881 has 27 divisors (see below), whose sum is σ = 18203716713. Its totient is φ = 7855423560.

The previous prime is 12186172871. The next prime is 12186172891. The reversal of 12186172881 is 18827168121.

The square root of 12186172881 is 110391.

It is a perfect power (a square), and thus also a powerful number.

12186172881 is a `hidden beast` number, since 1 + 2 + 1 + 8 + 617 + 28 + 8 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (12186172871) and next prime (12186172891).

It is not a de Polignac number, because 12186172881 - 2⁷ = 12186172753 is a prime.

It is a super-2 number, since 2×12186172881² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (12186172811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 10265770 + ... + 10266956.

Almost surely, 2^12186172881 is an apocalyptic number.

12186172881 is the 110391-st square number.

12186172881 is the 55196-th centered octagonal number.

It is an amenable number.

12186172881 is a deficient number, since it is larger than the sum of its proper divisors (6017543832).

12186172881 is an frugal number, since it uses more digits than its factorization.

12186172881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2442 (or 1221 counting only the distinct ones).

The product of its digits is 86016, while the sum is 45.

The spelling of 12186172881 in words is "twelve billion, one hundred eighty-six million, one hundred seventy-two thousand, eight hundred eighty-one".