47809 has 2 divisors, whose sum is σ = 47810. Its totient is φ = 47808.

The previous prime is 47807. The next prime is 47819. The reversal of 47809 is 90874.

47809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29584 + 18225 = 172^2 + 135^2 .

It is a cyclic number.

It is not a de Polignac number, because 47809 - 2¹ = 47807 is a prime.

Together with 47807, it forms a pair of twin primes.

It is a Chen prime.

It is a plaindrome in base 14.

It is not a weakly prime, because it can be changed into another prime (47807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23904 + 23905.

It is an arithmetic number, because the mean of its divisors is an integer number (23905).

2⁴⁷⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

47809 is a deficient number, since it is larger than the sum of its proper divisors (1).

47809 is an equidigital number, since it uses as much as digits as its factorization.

47809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 47809 is about 218.6526926429. The cubic root of 47809 is about 36.2941436062.

The spelling of 47809 in words is "forty-seven thousand, eight hundred nine".