81202981841 has 2 divisors, whose sum is σ = 81202981842. Its totient is φ = 81202981840.

The previous prime is 81202981829. The next prime is 81202981903. The reversal of 81202981841 is 14818920218.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 67806076816 + 13396905025 = 260396^2 + 115745^2 .

It is a cyclic number.

It is not a de Polignac number, because 81202981841 - 2³⁰ = 80129240017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81202981792 and 81202981801.

It is not a weakly prime, because it can be changed into another prime (81202981441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40601490920 + 40601490921.

It is an arithmetic number, because the mean of its divisors is an integer number (40601490921).

Almost surely, 2^81202981841 is an apocalyptic number.

It is an amenable number.

81202981841 is a deficient number, since it is larger than the sum of its proper divisors (1).

81202981841 is an equidigital number, since it uses as much as digits as its factorization.

81202981841 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 73728, while the sum is 44.

The spelling of 81202981841 in words is "eighty-one billion, two hundred two million, nine hundred eighty-one thousand, eight hundred forty-one".