20500247 has 2 divisors, whose sum is σ = 20500248. Its totient is φ = 20500246.

The previous prime is 20500231. The next prime is 20500279. The reversal of 20500247 is 74200502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20500247 - 2⁴ = 20500231 is a prime.

It is a super-2 number, since 2×20500247² = 840520254122018, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20500217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10250123 + 10250124.

It is an arithmetic number, because the mean of its divisors is an integer number (10250124).

Almost surely, 2^20500247 is an apocalyptic number.

20500247 is a deficient number, since it is larger than the sum of its proper divisors (1).

20500247 is an equidigital number, since it uses as much as digits as its factorization.

20500247 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 560, while the sum is 20.

The square root of 20500247 is about 4527.7198455735. The cubic root of 20500247 is about 273.6862829264.

Adding to 20500247 its reverse (74200502), we get a palindrome (94700749).

The spelling of 20500247 in words is "twenty million, five hundred thousand, two hundred forty-seven".