20591317 has 2 divisors, whose sum is σ = 20591318. Its totient is φ = 20591316.

The previous prime is 20591303. The next prime is 20591339. The reversal of 20591317 is 71319502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15689521 + 4901796 = 3961^2 + 2214^2 .

It is a cyclic number.

It is not a de Polignac number, because 20591317 - 2¹⁹ = 20067029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20591377) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10295658 + 10295659.

It is an arithmetic number, because the mean of its divisors is an integer number (10295659).

Almost surely, 2^20591317 is an apocalyptic number.

It is an amenable number.

20591317 is a deficient number, since it is larger than the sum of its proper divisors (1).

20591317 is an equidigital number, since it uses as much as digits as its factorization.

20591317 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1890, while the sum is 28.

The square root of 20591317 is about 4537.7656396072. The cubic root of 20591317 is about 274.0909576012.

The spelling of 20591317 in words is "twenty million, five hundred ninety-one thousand, three hundred seventeen".