409561 has 4 divisors (see below), whose sum is σ = 427392. Its totient is φ = 391732.

The previous prime is 409543. The next prime is 409573. The reversal of 409561 is 165904.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 409561 - 2⁵ = 409529 is a prime.

It is a Duffinian number.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (409261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8881 + ... + 8926.

It is an arithmetic number, because the mean of its divisors is an integer number (106848).

2⁴⁰⁹⁵⁶¹ is an apocalyptic number.

It is an amenable number.

409561 is a deficient number, since it is larger than the sum of its proper divisors (17831).

409561 is a wasteful number, since it uses less digits than its factorization.

409561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17830.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 409561 is about 639.9695305247. The cubic root of 409561 is about 74.2630642062.

The spelling of 409561 in words is "four hundred nine thousand, five hundred sixty-one".