221898464321 has 2 divisors, whose sum is σ = 221898464322. Its totient is φ = 221898464320.

The previous prime is 221898464213. The next prime is 221898464327. The reversal of 221898464321 is 123464898122.

221898464321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with previous prime (221898464213) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 123035383696 + 98863080625 = 350764^2 + 314425^2 .

It is a cyclic number.

It is not a de Polignac number, because 221898464321 - 2¹⁸ = 221898202177 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221898464321.

It is not a weakly prime, because it can be changed into another prime (221898464327) 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, 110949232160 + 110949232161.

It is an arithmetic number, because the mean of its divisors is an integer number (110949232161).

Almost surely, 2^221898464321 is an apocalyptic number.

It is an amenable number.

221898464321 is a deficient number, since it is larger than the sum of its proper divisors (1).

221898464321 is an equidigital number, since it uses as much as digits as its factorization.

221898464321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1327104, while the sum is 50.

The spelling of 221898464321 in words is "two hundred twenty-one billion, eight hundred ninety-eight million, four hundred sixty-four thousand, three hundred twenty-one".