409091 has 4 divisors (see below), whose sum is σ = 410712. Its totient is φ = 407472.

The previous prime is 409081. The next prime is 409099. The reversal of 409091 is 190904.

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

It is a cyclic number.

It is not a de Polignac number, because 409091 - 2⁶ = 409027 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a zygodrome in base 2.

It is not an unprimeable number, because it can be changed into a prime (409099) 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, 341 + ... + 966.

It is an arithmetic number, because the mean of its divisors is an integer number (102678).

2⁴⁰⁹⁰⁹¹ is an apocalyptic number.

409091 is a deficient number, since it is larger than the sum of its proper divisors (1621).

409091 is a wasteful number, since it uses less digits than its factorization.

409091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1620.

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 409091 is about 639.6022201337. The cubic root of 409091 is about 74.2346459729.

Adding to 409091 its reverse (190904), we get a palindrome (599995).

The spelling of 409091 in words is "four hundred nine thousand, ninety-one".