20829 has 8 divisors (see below), whose sum is σ = 28512. Its totient is φ = 13520.

The previous prime is 20809. The next prime is 20849. The reversal of 20829 is 92802.

20829 is nontrivially palindromic in base 9.

It is an interprime number because it is at equal distance from previous prime (20809) and next prime (20849).

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 20829 - 2¹³ = 12637 is a prime.

It is a Curzon number.

It is a nialpdrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20809) 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, 94 + ... + 224.

It is an arithmetic number, because the mean of its divisors is an integer number (3564).

2²⁰⁸²⁹ is an apocalyptic number.

It is an amenable number.

20829 is a deficient number, since it is larger than the sum of its proper divisors (7683).

20829 is a wasteful number, since it uses less digits than its factorization.

20829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 20829 is about 144.3225554097. The cubic root of 20829 is about 27.5141524950.

The spelling of 20829 in words is "twenty thousand, eight hundred twenty-nine".