64409 has 4 divisors (see below), whose sum is σ = 66660. Its totient is φ = 62160.

The previous prime is 64403. The next prime is 64433. The reversal of 64409 is 90446.

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

It can be written as a sum of positive squares in 2 ways, for example, as 38809 + 25600 = 197^2 + 160^2 .

It is a cyclic number.

It is not a de Polignac number, because 64409 - 2⁸ = 64153 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (64403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1082 + ... + 1139.

It is an arithmetic number, because the mean of its divisors is an integer number (16665).

2⁶⁴⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

64409 is a deficient number, since it is larger than the sum of its proper divisors (2251).

64409 is a wasteful number, since it uses less digits than its factorization.

64409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2250.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 64409 is about 253.7892826736. The cubic root of 64409 is about 40.0850274635.

The spelling of 64409 in words is "sixty-four thousand, four hundred nine".