1004405220 has 288 divisors, whose sum is σ = 3971455488. Its totient is φ = 199397376.

The previous prime is 1004405191. The next prime is 1004405231. The reversal of 1004405220 is 225044001.

1004405220 is a `hidden beast` number, since 1 + 0 + 0 + 440 + 5 + 220 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 1004405193 and 1004405202.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 276657 + ... + 280263.

It is an arithmetic number, because the mean of its divisors is an integer number (13789776).

Almost surely, 2^1004405220 is an apocalyptic number.

1004405220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1004405220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1985727744).

1004405220 is an abundant number, since it is smaller than the sum of its proper divisors (2967050268).

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

1004405220 is a wasteful number, since it uses less digits than its factorization.

1004405220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3659 (or 3654 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 1004405220 is about 31692.3527053452. The cubic root of 1004405220 is about 1001.4662557101.

Adding to 1004405220 its reverse (225044001), we get a palindrome (1229449221).

The spelling of 1004405220 in words is "one billion, four million, four hundred five thousand, two hundred twenty".