405001220 has 48 divisors (see below), whose sum is σ = 917395248. Its totient is φ = 149299200.

The previous prime is 405001199. The next prime is 405001229. The reversal of 405001220 is 22100504.

405001220 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 29571844 + 375429376 = 5438^2 + 19376^2 .

It is a junction number, because it is equal to n+sod(n) for n = 405001195 and 405001204.

It is not an unprimeable number, because it can be changed into a prime (405001229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 311612 + ... + 312908.

It is an arithmetic number, because the mean of its divisors is an integer number (19112401).

Almost surely, 2^405001220 is an apocalyptic number.

It is an amenable number.

405001220 is an abundant number, since it is smaller than the sum of its proper divisors (512394028).

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

405001220 is a wasteful number, since it uses less digits than its factorization.

405001220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2520 (or 2518 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 405001220 is about 20124.6421086190. The cubic root of 405001220 is about 739.8643652067.

Adding to 405001220 its reverse (22100504), we get a palindrome (427101724).

The spelling of 405001220 in words is "four hundred five million, one thousand, two hundred twenty".