18328863221 has 2 divisors, whose sum is σ = 18328863222. Its totient is φ = 18328863220.

The previous prime is 18328863121. The next prime is 18328863227. The reversal of 18328863221 is 12236882381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14276904196 + 4051959025 = 119486^2 + 63655^2 .

It is a cyclic number.

It is not a de Polignac number, because 18328863221 - 2¹⁰ = 18328862197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18328863227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9164431610 + 9164431611.

It is an arithmetic number, because the mean of its divisors is an integer number (9164431611).

Almost surely, 2^18328863221 is an apocalyptic number.

It is an amenable number.

18328863221 is a deficient number, since it is larger than the sum of its proper divisors (1).

18328863221 is an equidigital number, since it uses as much as digits as its factorization.

18328863221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 221184, while the sum is 44.

The spelling of 18328863221 in words is "eighteen billion, three hundred twenty-eight million, eight hundred sixty-three thousand, two hundred twenty-one".