1004400520 has 32 divisors (see below), whose sum is σ = 2320983000. Its totient is φ = 390901248.

The previous prime is 1004400491. The next prime is 1004400559. The reversal of 1004400520 is 250044001.

It can be written as a sum of positive squares in 4 ways, for example, as 786129444 + 218271076 = 28038^2 + 14774^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1004400494 and 1004400503.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 337845 + ... + 340804.

Almost surely, 2^1004400520 is an apocalyptic number.

1004400520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1004400520 is an abundant number, since it is smaller than the sum of its proper divisors (1316582480).

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

1004400520 is a wasteful number, since it uses less digits than its factorization.

1004400520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 678697 (or 678693 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 16.

The square root of 1004400520 is about 31692.2785548783. The cubic root of 1004400520 is about 1001.4646936252.

Adding to 1004400520 its reverse (250044001), we get a palindrome (1254444521).

The spelling of 1004400520 in words is "one billion, four million, four hundred thousand, five hundred twenty".