20317247 has 2 divisors, whose sum is σ = 20317248. Its totient is φ = 20317246.

The previous prime is 20317229. The next prime is 20317249. The reversal of 20317247 is 74271302.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20317247 - 2⁸ = 20316991 is a prime.

Together with 20317249, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20317249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10158623 + 10158624.

It is an arithmetic number, because the mean of its divisors is an integer number (10158624).

Almost surely, 2^20317247 is an apocalyptic number.

20317247 is a deficient number, since it is larger than the sum of its proper divisors (1).

20317247 is an equidigital number, since it uses as much as digits as its factorization.

20317247 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2352, while the sum is 26.

The square root of 20317247 is about 4507.4656959316. The cubic root of 20317247 is about 272.8694738462.

Adding to 20317247 its reverse (74271302), we get a palindrome (94588549).

The spelling of 20317247 in words is "twenty million, three hundred seventeen thousand, two hundred forty-seven".