404004090 has 128 divisors (see below), whose sum is σ = 1153105920. Its totient is φ = 88646400.

The previous prime is 404004061. The next prime is 404004091. The reversal of 404004090 is 90400404.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (404004091) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1490655 + ... + 1490925.

It is an arithmetic number, because the mean of its divisors is an integer number (9008640).

Almost surely, 2^404004090 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 404004090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (576552960).

404004090 is an abundant number, since it is smaller than the sum of its proper divisors (749101830).

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

404004090 is a wasteful number, since it uses less digits than its factorization.

404004090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548.

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 404004090 is about 20099.8529845370. The cubic root of 404004090 is about 739.2566738408.

Adding to 404004090 its reverse (90400404), we get a palindrome (494404494).

The spelling of 404004090 in words is "four hundred four million, four thousand, ninety".