12187927261 has 2 divisors, whose sum is σ = 12187927262. Its totient is φ = 12187927260.

The previous prime is 12187927259. The next prime is 12187927277. The reversal of 12187927261 is 16272978121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12186835236 + 1092025 = 110394^2 + 1045^2 .

It is an emirp because it is prime and its reverse (16272978121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12187927261 - 2¹ = 12187927259 is a prime.

Together with 12187927259, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12187927291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6093963630 + 6093963631.

It is an arithmetic number, because the mean of its divisors is an integer number (6093963631).

Almost surely, 2^12187927261 is an apocalyptic number.

It is an amenable number.

12187927261 is a deficient number, since it is larger than the sum of its proper divisors (1).

12187927261 is an equidigital number, since it uses as much as digits as its factorization.

12187927261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 169344, while the sum is 46.

The spelling of 12187927261 in words is "twelve billion, one hundred eighty-seven million, nine hundred twenty-seven thousand, two hundred sixty-one".