8381355033221 has 2 divisors, whose sum is σ = 8381355033222. Its totient is φ = 8381355033220.

The previous prime is 8381355033199. The next prime is 8381355033239. The reversal of 8381355033221 is 1223305531838.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8158935268225 + 222419764996 = 2856385^2 + 471614^2 .

It is a cyclic number.

It is not a de Polignac number, because 8381355033221 - 2²⁶ = 8381287924357 is a prime.

It is a super-2 number, since 2×8381355033221² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8381355033251) 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, 4190677516610 + 4190677516611.

It is an arithmetic number, because the mean of its divisors is an integer number (4190677516611).

Almost surely, 2^{8381355033221} is an apocalyptic number.

It is an amenable number.

8381355033221 is a deficient number, since it is larger than the sum of its proper divisors (1).

8381355033221 is an equidigital number, since it uses as much as digits as its factorization.

8381355033221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 518400, while the sum is 44.

The spelling of 8381355033221 in words is "eight trillion, three hundred eighty-one billion, three hundred fifty-five million, thirty-three thousand, two hundred twenty-one".