81436211 has 2 divisors, whose sum is σ = 81436212. Its totient is φ = 81436210.

The previous prime is 81436193. The next prime is 81436237. The reversal of 81436211 is 11263418.

It is an a-pointer prime, because the next prime (81436237) can be obtained adding 81436211 to its sum of digits (26).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81436211 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (81436241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40718105 + 40718106.

It is an arithmetic number, because the mean of its divisors is an integer number (40718106).

Almost surely, 2^81436211 is an apocalyptic number.

81436211 is a deficient number, since it is larger than the sum of its proper divisors (1).

81436211 is an equidigital number, since it uses as much as digits as its factorization.

81436211 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 26.

The square root of 81436211 is about 9024.2014051106. The cubic root of 81436211 is about 433.4501786813.

Adding to 81436211 its reverse (11263418), we get a palindrome (92699629).

The spelling of 81436211 in words is "eighty-one million, four hundred thirty-six thousand, two hundred eleven".