404808921 has 20 divisors (see below), whose sum is σ = 659690064. Its totient is φ = 245338200.

The previous prime is 404808917. The next prime is 404808931. The reversal of 404808921 is 129808404.

It is not a de Polignac number, because 404808921 - 2² = 404808917 is a prime.

It is not an unprimeable number, because it can be changed into a prime (404808931) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 226275 + ... + 228056.

Almost surely, 2^404808921 is an apocalyptic number.

It is an amenable number.

404808921 is a deficient number, since it is larger than the sum of its proper divisors (254881143).

404808921 is a wasteful number, since it uses less digits than its factorization.

404808921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 454354 (or 454345 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 404808921 is about 20119.8638414876. The cubic root of 404808921 is about 739.7472481098.

The spelling of 404808921 in words is "four hundred four million, eight hundred eight thousand, nine hundred twenty-one".