20113 has 2 divisors, whose sum is σ = 20114. Its totient is φ = 20112.

The previous prime is 20107. The next prime is 20117. The reversal of 20113 is 31102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12544 + 7569 = 112^2 + 87^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20113 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20096 and 20105.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10056 + 10057.

It is an arithmetic number, because the mean of its divisors is an integer number (10057).

2²⁰¹¹³ is an apocalyptic number.

It is an amenable number.

20113 is a deficient number, since it is larger than the sum of its proper divisors (1).

20113 is an equidigital number, since it uses as much as digits as its factorization.

20113 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6, while the sum is 7.

The square root of 20113 is about 141.8203088419. The cubic root of 20113 is about 27.1952017199.

Adding to 20113 its reverse (31102), we get a palindrome (51215).

The spelling of 20113 in words is "twenty thousand, one hundred thirteen".