20123 has 2 divisors, whose sum is σ = 20124. Its totient is φ = 20122.

The previous prime is 20117. The next prime is 20129. The reversal of 20123 is 32102.

It is a balanced prime because it is at equal distance from previous prime (20117) and next prime (20129).

It is a cyclic number.

It is not a de Polignac number, because 20123 - 2⁴ = 20107 is a prime.

It is a plaindrome in base 7.

It is a self number, because there is not a number n which added to its sum of digits gives 20123.

It is not a weakly prime, because it can be changed into another prime (20129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10061 + 10062.

It is an arithmetic number, because the mean of its divisors is an integer number (10062).

2²⁰¹²³ is an apocalyptic number.

20123 is a deficient number, since it is larger than the sum of its proper divisors (1).

20123 is an equidigital number, since it uses as much as digits as its factorization.

20123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12, while the sum is 8.

The square root of 20123 is about 141.8555603422. The cubic root of 20123 is about 27.1997080418.

Adding to 20123 its reverse (32102), we get a palindrome (52225).

The spelling of 20123 in words is "twenty thousand, one hundred twenty-three", and thus it is an iban number.