405330221 has 2 divisors, whose sum is σ = 405330222. Its totient is φ = 405330220.

The previous prime is 405330199. The next prime is 405330241. The reversal of 405330221 is 122033504.

It is a happy number.

It is an a-pointer prime, because the next prime (405330241) can be obtained adding 405330221 to its sum of digits (20).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 243048100 + 162282121 = 15590^2 + 12739^2 .

It is a cyclic number.

It is not a de Polignac number, because 405330221 - 2⁶ = 405330157 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 405330193 and 405330202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (405330241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202665110 + 202665111.

It is an arithmetic number, because the mean of its divisors is an integer number (202665111).

Almost surely, 2^405330221 is an apocalyptic number.

It is an amenable number.

405330221 is a deficient number, since it is larger than the sum of its proper divisors (1).

405330221 is an equidigital number, since it uses as much as digits as its factorization.

405330221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 405330221 is about 20132.8145324989. The cubic root of 405330221 is about 740.0646528611.

Adding to 405330221 its reverse (122033504), we get a palindrome (527363725).

The spelling of 405330221 in words is "four hundred five million, three hundred thirty thousand, two hundred twenty-one".