20000257 has 4 divisors (see below), whose sum is σ = 20023216. Its totient is φ = 19977300.

The previous prime is 20000243. The next prime is 20000269. The reversal of 20000257 is 75200002.

It is a happy number.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20000257 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20000257.

It is not an unprimeable number, because it can be changed into a prime (20000287) 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, 10119 + ... + 11932.

It is an arithmetic number, because the mean of its divisors is an integer number (5005804).

Almost surely, 2^20000257 is an apocalyptic number.

It is an amenable number.

20000257 is a deficient number, since it is larger than the sum of its proper divisors (22959).

20000257 is an equidigital number, since it uses as much as digits as its factorization.

20000257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22958.

The product of its (nonzero) digits is 140, while the sum is 16.

The square root of 20000257 is about 4472.1646883808. The cubic root of 20000257 is about 271.4429243301.

Adding to 20000257 its reverse (75200002), we get a palindrome (95200259).

The spelling of 20000257 in words is "twenty million, two hundred fifty-seven", and thus it is an aban number.