12891811 has 2 divisors, whose sum is σ = 12891812. Its totient is φ = 12891810.

The previous prime is 12891803. The next prime is 12891829. The reversal of 12891811 is 11819821.

12891811 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12891811 - 2³ = 12891803 is a prime.

It is not a weakly prime, because it can be changed into another prime (12891871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6445905 + 6445906.

It is an arithmetic number, because the mean of its divisors is an integer number (6445906).

Almost surely, 2^12891811 is an apocalyptic number.

12891811 is a deficient number, since it is larger than the sum of its proper divisors (1).

12891811 is an equidigital number, since it uses as much as digits as its factorization.

12891811 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 31.

The square root of 12891811 is about 3590.5168151674. The cubic root of 12891811 is about 234.4793725595.

The spelling of 12891811 in words is "twelve million, eight hundred ninety-one thousand, eight hundred eleven".