404004020 has 36 divisors (see below), whose sum is σ = 986926500. Its totient is φ = 138515328.

The previous prime is 404003983. The next prime is 404004023. The reversal of 404004020 is 20400404.

It can be written as a sum of positive squares in 2 ways, for example, as 52591504 + 351412516 = 7252^2 + 18746^2 .

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 404003986 and 404004004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (404004023) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 205145 + ... + 207104.

It is an arithmetic number, because the mean of its divisors is an integer number (27414625).

Almost surely, 2^404004020 is an apocalyptic number.

It is an amenable number.

404004020 is an abundant number, since it is smaller than the sum of its proper divisors (582922480).

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

404004020 is a wasteful number, since it uses less digits than its factorization.

404004020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 412272 (or 412263 counting only the distinct ones).

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

The square root of 404004020 is about 20099.8512432306. The cubic root of 404004020 is about 739.2566311449.

Adding to 404004020 its reverse (20400404), we get a palindrome (424404424).

The spelling of 404004020 in words is "four hundred four million, four thousand, twenty".