288409 has 8 divisors (see below), whose sum is σ = 318528. Its totient is φ = 258960.

The previous prime is 288403. The next prime is 288413. The reversal of 288409 is 904882.

288409 = 77² + 78² + ... + 109².

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

It is a cyclic number.

It is not a de Polignac number, because 288409 - 2¹⁵ = 255641 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (288403) 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, 1644 + ... + 1810.

It is an arithmetic number, because the mean of its divisors is an integer number (39816).

2²⁸⁸⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

288409 is a deficient number, since it is larger than the sum of its proper divisors (30119).

288409 is a wasteful number, since it uses less digits than its factorization.

288409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 335.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 288409 is about 537.0372426564. The cubic root of 288409 is about 66.0697914931.

It can be divided in two parts, 28840 and 9, that multiplied together give a triangular number (259560 = T₇₂₀).

The spelling of 288409 in words is "two hundred eighty-eight thousand, four hundred nine".