81818102893 has 2 divisors, whose sum is σ = 81818102894. Its totient is φ = 81818102892.

The previous prime is 81818102887. The next prime is 81818102953. The reversal of 81818102893 is 39820181818.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 74339658409 + 7478444484 = 272653^2 + 86478^2 .

It is a cyclic number.

It is not a de Polignac number, because 81818102893 - 2²⁹ = 81281231981 is a prime.

It is a super-2 number, since 2×81818102893² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81818102593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40909051446 + 40909051447.

It is an arithmetic number, because the mean of its divisors is an integer number (40909051447).

Almost surely, 2^81818102893 is an apocalyptic number.

It is an amenable number.

81818102893 is a deficient number, since it is larger than the sum of its proper divisors (1).

81818102893 is an equidigital number, since it uses as much as digits as its factorization.

81818102893 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 221184, while the sum is 49.

The spelling of 81818102893 in words is "eighty-one billion, eight hundred eighteen million, one hundred two thousand, eight hundred ninety-three".