291409 has 4 divisors (see below), whose sum is σ = 292516. Its totient is φ = 290304.

The previous prime is 291377. The next prime is 291419. The reversal of 291409 is 904192.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 61009 + 230400 = 247^2 + 480^2 .

It is a cyclic number.

It is not a de Polignac number, because 291409 - 2⁵ = 291377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (291419) 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, 97 + ... + 769.

It is an arithmetic number, because the mean of its divisors is an integer number (73129).

2²⁹¹⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

291409 is a deficient number, since it is larger than the sum of its proper divisors (1107).

291409 is an equidigital number, since it uses as much as digits as its factorization.

291409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1106.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 291409 is about 539.8231191789. The cubic root of 291409 is about 66.2980854178.

The spelling of 291409 in words is "two hundred ninety-one thousand, four hundred nine".