409661 has 8 divisors (see below), whose sum is σ = 479424. Its totient is φ = 342720.

The previous prime is 409657. The next prime is 409691. The reversal of 409661 is 166904.

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

It is not a de Polignac number, because 409661 - 2² = 409657 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 409661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (409691) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 380 + ... + 981.

It is an arithmetic number, because the mean of its divisors is an integer number (59928).

2⁴⁰⁹⁶⁶¹ is an apocalyptic number.

It is an amenable number.

409661 is a deficient number, since it is larger than the sum of its proper divisors (69763).

409661 is a wasteful number, since it uses less digits than its factorization.

409661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1411.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 409661 is about 640.0476544758. The cubic root of 409661 is about 74.2691078334.

The spelling of 409661 in words is "four hundred nine thousand, six hundred sixty-one".