408921 has 8 divisors (see below), whose sum is σ = 562944. Its totient is φ = 263760.

The previous prime is 408913. The next prime is 408923. The reversal of 408921 is 129804.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 408921 - 2³ = 408913 is a prime.

408921 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 408891 and 408900.

It is not an unprimeable number, because it can be changed into a prime (408923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2106 + ... + 2291.

It is an arithmetic number, because the mean of its divisors is an integer number (70368).

2⁴⁰⁸⁹²¹ is an apocalyptic number.

It is an amenable number.

408921 is a deficient number, since it is larger than the sum of its proper divisors (154023).

408921 is a wasteful number, since it uses less digits than its factorization.

408921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4431.

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 408921 is about 639.4693112261. The cubic root of 408921 is about 74.2243616773.

The spelling of 408921 in words is "four hundred eight thousand, nine hundred twenty-one".