404020040 has 16 divisors (see below), whose sum is σ = 909045180. Its totient is φ = 161608000.

The previous prime is 404020031. The next prime is 404020049. The reversal of 404020040 is 40020404.

It is an interprime number because it is at equal distance from previous prime (404020031) and next prime (404020049).

It can be written as a sum of positive squares in 2 ways, for example, as 395293924 + 8726116 = 19882^2 + 2954^2 .

It is a junction number, because it is equal to n+sod(n) for n = 404019997 and 404020024.

It is not an unprimeable number, because it can be changed into a prime (404020049) 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, 5050211 + ... + 5050290.

Almost surely, 2^404020040 is an apocalyptic number.

404020040 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

404020040 is an abundant number, since it is smaller than the sum of its proper divisors (505025140).

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

404020040 is a wasteful number, since it uses less digits than its factorization.

404020040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10100512 (or 10100508 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 14.

The square root of 404020040 is about 20100.2497496922. The cubic root of 404020040 is about 739.2664022809.

Adding to 404020040 its reverse (40020404), we get a palindrome (444040444).

The spelling of 404020040 in words is "four hundred four million, twenty thousand, forty".