405220 has 12 divisors (see below), whose sum is σ = 851004. Its totient is φ = 162080.

The previous prime is 405211. The next prime is 405221. The reversal of 405220 is 22504.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 54756 + 350464 = 234^2 + 592^2 .

It is a plaindrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 405220.

It is not an unprimeable number, because it can be changed into a prime (405221) 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, 10111 + ... + 10150.

It is an arithmetic number, because the mean of its divisors is an integer number (70917).

2⁴⁰⁵²²⁰ is an apocalyptic number.

It is an amenable number.

405220 is an abundant number, since it is smaller than the sum of its proper divisors (445784).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

405220 is a wasteful number, since it uses less digits than its factorization.

405220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20270 (or 20268 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 13.

The square root of 405220 is about 636.5689279253. The cubic root of 405220 is about 73.9997565125. Note that the first 3 decimals are identical.

Adding to 405220 its reverse (22504), we get a palindrome (427724).

It can be divided in two parts, 405 and 220, that added together give a 4-th power (625 = 5⁴).

The spelling of 405220 in words is "four hundred five thousand, two hundred twenty".