404400040 has 64 divisors (see below), whose sum is σ = 994757760. Its totient is φ = 146737920.

The previous prime is 404400023. The next prime is 404400043. The reversal of 404400040 is 40004404.

404400040 = 189² + 190² + ... + 1068².

It is a junction number, because it is equal to n+sod(n) for n = 404399987 and 404400023.

It is not an unprimeable number, because it can be changed into a prime (404400043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 326302 + ... + 327538.

It is an arithmetic number, because the mean of its divisors is an integer number (15543090).

Almost surely, 2^404400040 is an apocalyptic number.

404400040 is a gapful number since it is divisible by the number (40) 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 404400040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (497378880).

404400040 is an abundant number, since it is smaller than the sum of its proper divisors (590357720).

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

404400040 is a wasteful number, since it uses less digits than its factorization.

404400040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2002 (or 1998 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 16.

The square root of 404400040 is about 20109.7001469440. The cubic root of 404400040 is about 739.4981013534.

Adding to 404400040 its reverse (40004404), we get a palindrome (444404444).

The spelling of 404400040 in words is "four hundred four million, four hundred thousand, forty".