20007257 has 2 divisors, whose sum is σ = 20007258. Its totient is φ = 20007256.

The previous prime is 20007223. The next prime is 20007259. The reversal of 20007257 is 75270002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19855936 + 151321 = 4456^2 + 389^2 .

It is a cyclic number.

It is not a de Polignac number, because 20007257 - 2¹² = 20003161 is a prime.

Together with 20007259, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20007259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10003628 + 10003629.

It is an arithmetic number, because the mean of its divisors is an integer number (10003629).

Almost surely, 2^20007257 is an apocalyptic number.

It is an amenable number.

20007257 is a deficient number, since it is larger than the sum of its proper divisors (1).

20007257 is an equidigital number, since it uses as much as digits as its factorization.

20007257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 980, while the sum is 23.

The square root of 20007257 is about 4472.9472386783. The cubic root of 20007257 is about 271.4745885705.

Adding to 20007257 its reverse (75270002), we get a palindrome (95277259).

The spelling of 20007257 in words is "twenty million, seven thousand, two hundred fifty-seven".