420685 has 4 divisors (see below), whose sum is σ = 504828. Its totient is φ = 336544.

The previous prime is 420683. The next prime is 420691. The reversal of 420685 is 586024.

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 259081 + 161604 = 509^2 + 402^2 .

It is a cyclic number.

It is not a de Polignac number, because 420685 - 2¹ = 420683 is a prime.

It is a Duffinian number.

420685 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42064 + ... + 42073.

It is an arithmetic number, because the mean of its divisors is an integer number (126207).

2⁴²⁰⁶⁸⁵ is an apocalyptic number.

It is an amenable number.

420685 is a deficient number, since it is larger than the sum of its proper divisors (84143).

420685 is an equidigital number, since it uses as much as digits as its factorization.

420685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84142.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 420685 is about 648.6023435049. The cubic root of 420685 is about 74.9294150726.

The spelling of 420685 in words is "four hundred twenty thousand, six hundred eighty-five".