421302221 has 2 divisors, whose sum is σ = 421302222. Its totient is φ = 421302220.

The previous prime is 421302197. The next prime is 421302251. The reversal of 421302221 is 122203124.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 311346025 + 109956196 = 17645^2 + 10486^2 .

It is a cyclic number.

It is not a de Polignac number, because 421302221 - 2²² = 417107917 is a prime.

It is a super-2 number, since 2×421302221² = 354991122839065682, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 421302221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (421302251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210651110 + 210651111.

It is an arithmetic number, because the mean of its divisors is an integer number (210651111).

Almost surely, 2^421302221 is an apocalyptic number.

It is an amenable number.

421302221 is a deficient number, since it is larger than the sum of its proper divisors (1).

421302221 is an equidigital number, since it uses as much as digits as its factorization.

421302221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 421302221 is about 20525.6478825883. The cubic root of 421302221 is about 749.6604216794.

Adding to 421302221 its reverse (122203124), we get a palindrome (543505345).

The spelling of 421302221 in words is "four hundred twenty-one million, three hundred two thousand, two hundred twenty-one".