420305 has 4 divisors (see below), whose sum is σ = 504372. Its totient is φ = 336240.

The previous prime is 420293. The next prime is 420307. The reversal of 420305 is 503024.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 61504 + 358801 = 248^2 + 599^2 .

It is not a de Polignac number, because 420305 - 2⁶ = 420241 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 420305.

It is not an unprimeable number, because it can be changed into a prime (420307) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42026 + ... + 42035.

It is an arithmetic number, because the mean of its divisors is an integer number (126093).

2⁴²⁰³⁰⁵ is an apocalyptic number.

It is an amenable number.

420305 is a deficient number, since it is larger than the sum of its proper divisors (84067).

420305 is an equidigital number, since it uses as much as digits as its factorization.

420305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84066.

The product of its (nonzero) digits is 120, while the sum is 14.

The square root of 420305 is about 648.3093397445. The cubic root of 420305 is about 74.9068473119.

Adding to 420305 its reverse (503024), we get a palindrome (923329).

The spelling of 420305 in words is "four hundred twenty thousand, three hundred five".