81804211 has 2 divisors, whose sum is σ = 81804212. Its totient is φ = 81804210.

The previous prime is 81804199. The next prime is 81804223. The reversal of 81804211 is 11240818.

It is a balanced prime because it is at equal distance from previous prime (81804199) and next prime (81804223).

It is a cyclic number.

It is not a de Polignac number, because 81804211 - 2⁵ = 81804179 is a prime.

It is not a weakly prime, because it can be changed into another prime (81804241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40902105 + 40902106.

It is an arithmetic number, because the mean of its divisors is an integer number (40902106).

Almost surely, 2^81804211 is an apocalyptic number.

81804211 is a deficient number, since it is larger than the sum of its proper divisors (1).

81804211 is an equidigital number, since it uses as much as digits as its factorization.

81804211 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 512, while the sum is 25.

The square root of 81804211 is about 9044.5680383311. The cubic root of 81804211 is about 434.1020999709.

The spelling of 81804211 in words is "eighty-one million, eight hundred four thousand, two hundred eleven".