10002221221981 has 2 divisors, whose sum is σ = 10002221221982. Its totient is φ = 10002221221980.

The previous prime is 10002221221939. The next prime is 10002221222129. The reversal of 10002221221981 is 18912212220001.

10002221221981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8697751148025 + 1304470073956 = 2949195^2 + 1142134^2 .

It is a cyclic number.

It is not a de Polignac number, because 10002221221981 - 2⁹ = 10002221221469 is a prime.

It is a super-5 number, since 5×10002221221981⁵ (a number of 66 digits) contains 55555 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10002221221781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5001110610990 + 5001110610991.

It is an arithmetic number, because the mean of its divisors is an integer number (5001110610991).

Almost surely, 2^{10002221221981} is an apocalyptic number.

It is an amenable number.

10002221221981 is a deficient number, since it is larger than the sum of its proper divisors (1).

10002221221981 is an equidigital number, since it uses as much as digits as its factorization.

10002221221981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 31.

Adding to 10002221221981 its reverse (18912212220001), we get a palindrome (28914433441982).

The spelling of 10002221221981 in words is "ten trillion, two billion, two hundred twenty-one million, two hundred twenty-one thousand, nine hundred eighty-one".