420164221 has 2 divisors, whose sum is σ = 420164222. Its totient is φ = 420164220.

The previous prime is 420164203. The next prime is 420164237. The reversal of 420164221 is 122461024.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 394459321 + 25704900 = 19861^2 + 5070^2 .

It is a cyclic number.

It is not a de Polignac number, because 420164221 - 2⁵ = 420164189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 420164192 and 420164201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (420164021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210082110 + 210082111.

It is an arithmetic number, because the mean of its divisors is an integer number (210082111).

Almost surely, 2^420164221 is an apocalyptic number.

It is an amenable number.

420164221 is a deficient number, since it is larger than the sum of its proper divisors (1).

420164221 is an equidigital number, since it uses as much as digits as its factorization.

420164221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 420164221 is about 20497.9077224969. The cubic root of 420164221 is about 748.9848315677.

The spelling of 420164221 in words is "four hundred twenty million, one hundred sixty-four thousand, two hundred twenty-one".