20479 has 2 divisors, whose sum is σ = 20480. Its totient is φ = 20478.

The previous prime is 20477. The next prime is 20483. The reversal of 20479 is 97402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20479 - 2¹ = 20477 is a prime.

Together with 20477, it forms a pair of twin primes.

It is a Chen prime.

It is a plaindrome in base 8 and base 16.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20477) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10239 + 10240.

It is an arithmetic number, because the mean of its divisors is an integer number (10240).

2²⁰⁴⁷⁹ is an apocalyptic number.

20479 is a deficient number, since it is larger than the sum of its proper divisors (1).

20479 is an equidigital number, since it uses as much as digits as its factorization.

20479 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 20479 is about 143.1048566611. The cubic root of 20479 is about 27.3591698333.

The spelling of 20479 in words is "twenty thousand, four hundred seventy-nine".