12261681871 has 4 divisors (see below), whose sum is σ = 12267627552. Its totient is φ = 12255736192.

The previous prime is 12261681857. The next prime is 12261681889. The reversal of 12261681871 is 17818616221.

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

It is a cyclic number.

It is not a de Polignac number, because 12261681871 - 2¹⁷ = 12261550799 is a prime.

It is a super-2 number, since 2×12261681871² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12261681821) 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, 2969746 + ... + 2973871.

It is an arithmetic number, because the mean of its divisors is an integer number (3066906888).

Almost surely, 2^12261681871 is an apocalyptic number.

12261681871 is a deficient number, since it is larger than the sum of its proper divisors (5945681).

12261681871 is an equidigital number, since it uses as much as digits as its factorization.

12261681871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5945680.

The product of its digits is 64512, while the sum is 43.

The spelling of 12261681871 in words is "twelve billion, two hundred sixty-one million, six hundred eighty-one thousand, eight hundred seventy-one".