4020400404 has 18 divisors (see below), whose sum is σ = 10162678890. Its totient is φ = 1340133456.

The previous prime is 4020400403. The next prime is 4020400409. The reversal of 4020400404 is 4040040204.

It is a happy number.

4020400404 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 4018292100 + 2108304 = 63390^2 + 1452^2 .

It is a tau number, because it is divible by the number of its divisors (18).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4020400403) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 55838859 + ... + 55838930.

Almost surely, 2^4020400404 is an apocalyptic number.

It is an amenable number.

4020400404 is an abundant number, since it is smaller than the sum of its proper divisors (6142278486).

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

4020400404 is a wasteful number, since it uses less digits than its factorization.

4020400404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111677799 (or 111677794 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 18.

The square root of 4020400404 is about 63406.6274454020. The cubic root of 4020400404 is about 1590.0951123832.

Adding to 4020400404 its reverse (4040040204), we get a palindrome (8060440608).

The spelling of 4020400404 in words is "four billion, twenty million, four hundred thousand, four hundred four".