420533209 has 2 divisors, whose sum is σ = 420533210. Its totient is φ = 420533208.

The previous prime is 420533171. The next prime is 420533237. The reversal of 420533209 is 902335024.

It is an a-pointer prime, because the next prime (420533237) can be obtained adding 420533209 to its sum of digits (28).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 338449609 + 82083600 = 18397^2 + 9060^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-420533209 is a prime.

It is not a weakly prime, because it can be changed into another prime (420533609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210266604 + 210266605.

It is an arithmetic number, because the mean of its divisors is an integer number (210266605).

Almost surely, 2^420533209 is an apocalyptic number.

It is an amenable number.

420533209 is a deficient number, since it is larger than the sum of its proper divisors (1).

420533209 is an equidigital number, since it uses as much as digits as its factorization.

420533209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6480, while the sum is 28.

The square root of 420533209 is about 20506.9063732197. The cubic root of 420533209 is about 749.2040201128.

The spelling of 420533209 in words is "four hundred twenty million, five hundred thirty-three thousand, two hundred nine".