404988 has 12 divisors (see below), whose sum is σ = 945000. Its totient is φ = 134992.

The previous prime is 404983. The next prime is 405001. The reversal of 404988 is 889404.

It is a tau number, because it is divible by the number of its divisors (12).

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is a plaindrome in base 13.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 404988.

It is not an unprimeable number, because it can be changed into a prime (404981) 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, 16863 + ... + 16886.

It is an arithmetic number, because the mean of its divisors is an integer number (78750).

2⁴⁰⁴⁹⁸⁸ is an apocalyptic number.

It is an amenable number.

404988 is an abundant number, since it is smaller than the sum of its proper divisors (540012).

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

404988 is a wasteful number, since it uses less digits than its factorization.

404988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33756 (or 33754 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 404988 is about 636.3866749076. The cubic root of 404988 is about 73.9856314932.

Subtracting 404988 from its reverse (889404), we obtain a square (484416 = 696²).

The spelling of 404988 in words is "four hundred four thousand, nine hundred eighty-eight".