20057 has 4 divisors (see below), whose sum is σ = 20736. Its totient is φ = 19380.

The previous prime is 20051. The next prime is 20063. The reversal of 20057 is 75002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 75002 = 2 ⋅37501.

It is an interprime number because it is at equal distance from previous prime (20051) and next prime (20063).

It is a cyclic number.

It is not a de Polignac number, because 20057 - 2⁶ = 19993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 293 + ... + 354.

It is an arithmetic number, because the mean of its divisors is an integer number (5184).

2²⁰⁰⁵⁷ is an apocalyptic number.

It is an amenable number.

20057 is a deficient number, since it is larger than the sum of its proper divisors (679).

20057 is an equidigital number, since it uses as much as digits as its factorization.

20057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 678.

The product of its (nonzero) digits is 70, while the sum is 14.

The square root of 20057 is about 141.6227382873. The cubic root of 20057 is about 27.1699386744.

Adding to 20057 its reverse (75002), we get a palindrome (95059).

Subtracting 20057 from its reverse (75002), we obtain a palindrome (54945).

The spelling of 20057 in words is "twenty thousand, fifty-seven".