20045257 has 2 divisors, whose sum is σ = 20045258. Its totient is φ = 20045256.

The previous prime is 20045243. The next prime is 20045279. The reversal of 20045257 is 75254002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18352656 + 1692601 = 4284^2 + 1301^2 .

It is a cyclic number.

It is not a de Polignac number, because 20045257 - 2²³ = 11656649 is a prime.

It is not a weakly prime, because it can be changed into another prime (20045237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10022628 + 10022629.

It is an arithmetic number, because the mean of its divisors is an integer number (10022629).

Almost surely, 2^20045257 is an apocalyptic number.

It is an amenable number.

20045257 is a deficient number, since it is larger than the sum of its proper divisors (1).

20045257 is an equidigital number, since it uses as much as digits as its factorization.

20045257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2800, while the sum is 25.

The square root of 20045257 is about 4477.1929822155. The cubic root of 20045257 is about 271.6463514152.

Adding to 20045257 its reverse (75254002), we get a palindrome (95299259).

It can be divided in two parts, 20045 and 257, that added together give a palindrome (20302).

The spelling of 20045257 in words is "twenty million, forty-five thousand, two hundred fifty-seven".