409855 has 4 divisors (see below), whose sum is σ = 491832. Its totient is φ = 327880.

The previous prime is 409841. The next prime is 409861. The reversal of 409855 is 558904.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 409855 - 2⁵ = 409823 is a prime.

It is a super-2 number, since 2×409855² = 335962242050, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 40981 + ... + 40990.

It is an arithmetic number, because the mean of its divisors is an integer number (122958).

2⁴⁰⁹⁸⁵⁵ is an apocalyptic number.

409855 is a deficient number, since it is larger than the sum of its proper divisors (81977).

409855 is an equidigital number, since it uses as much as digits as its factorization.

409855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81976.

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 409855 is about 640.1991877533. The cubic root of 409855 is about 74.2808296661.

The spelling of 409855 in words is "four hundred nine thousand, eight hundred fifty-five".