12361891 has 2 divisors, whose sum is σ = 12361892. Its totient is φ = 12361890.

The previous prime is 12361889. The next prime is 12361897. The reversal of 12361891 is 19816321.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12361891 - 2¹ = 12361889 is a prime.

Together with 12361889, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (12361897) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6180945 + 6180946.

It is an arithmetic number, because the mean of its divisors is an integer number (6180946).

Almost surely, 2^12361891 is an apocalyptic number.

12361891 is a deficient number, since it is larger than the sum of its proper divisors (1).

12361891 is an equidigital number, since it uses as much as digits as its factorization.

12361891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592, while the sum is 31.

The square root of 12361891 is about 3515.9480940423. The cubic root of 12361891 is about 231.2215474125.

The spelling of 12361891 in words is "twelve million, three hundred sixty-one thousand, eight hundred ninety-one".