12611891 has 2 divisors, whose sum is σ = 12611892. Its totient is φ = 12611890.

The previous prime is 12611869. The next prime is 12611903. The reversal of 12611891 is 19811621.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 12611891 - 2¹⁰ = 12610867 is a prime.

It is not a weakly prime, because it can be changed into another prime (12611821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6305945 + 6305946.

It is an arithmetic number, because the mean of its divisors is an integer number (6305946).

Almost surely, 2^12611891 is an apocalyptic number.

12611891 is a deficient number, since it is larger than the sum of its proper divisors (1).

12611891 is an equidigital number, since it uses as much as digits as its factorization.

12611891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 864, while the sum is 29.

The square root of 12611891 is about 3551.3224297436. The cubic root of 12611891 is about 232.7698550872.

The spelling of 12611891 in words is "twelve million, six hundred eleven thousand, eight hundred ninety-one".