818181818181853 has 2 divisors, whose sum is σ = 818181818181854. Its totient is φ = 818181818181852.

The previous prime is 818181818181839. The next prime is 818181818181869. The reversal of 818181818181853 is 358181818181818.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 569596552553284 + 248585265628569 = 23866222^2 + 15766587^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-818181818181853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (818181818181883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 409090909090926 + 409090909090927.

It is an arithmetic number, because the mean of its divisors is an integer number (409090909090927).

Almost surely, 2^{818181818181853} is an apocalyptic number.

It is an amenable number.

818181818181853 is a deficient number, since it is larger than the sum of its proper divisors (1).

818181818181853 is an equidigital number, since it uses as much as digits as its factorization.

818181818181853 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31457280, while the sum is 70.

The spelling of 818181818181853 in words is "eight hundred eighteen trillion, one hundred eighty-one billion, eight hundred eighteen million, one hundred eighty-one thousand, eight hundred fifty-three".