81825011 has 2 divisors, whose sum is σ = 81825012. Its totient is φ = 81825010.

The previous prime is 81824993. The next prime is 81825013. The reversal of 81825011 is 11052818.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81825011 - 2¹⁸ = 81562867 is a prime.

Together with 81825013, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (81825013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40912505 + 40912506.

It is an arithmetic number, because the mean of its divisors is an integer number (40912506).

Almost surely, 2^81825011 is an apocalyptic number.

81825011 is a deficient number, since it is larger than the sum of its proper divisors (1).

81825011 is an equidigital number, since it uses as much as digits as its factorization.

81825011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 640, while the sum is 26.

The square root of 81825011 is about 9045.7178266846. The cubic root of 81825011 is about 434.1388892690.

Adding to 81825011 its reverse (11052818), we get a palindrome (92877829).

The spelling of 81825011 in words is "eighty-one million, eight hundred twenty-five thousand, eleven".