20717449 has 2 divisors, whose sum is σ = 20717450. Its totient is φ = 20717448.

The previous prime is 20717419. The next prime is 20717453. The reversal of 20717449 is 94471702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17935225 + 2782224 = 4235^2 + 1668^2 .

It is a cyclic number.

It is not a de Polignac number, because 20717449 - 2²¹ = 18620297 is a prime.

It is not a weakly prime, because it can be changed into another prime (20717419) 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, 10358724 + 10358725.

It is an arithmetic number, because the mean of its divisors is an integer number (10358725).

Almost surely, 2^20717449 is an apocalyptic number.

It is an amenable number.

20717449 is a deficient number, since it is larger than the sum of its proper divisors (1).

20717449 is an equidigital number, since it uses as much as digits as its factorization.

20717449 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14112, while the sum is 34.

The square root of 20717449 is about 4551.6424508083. The cubic root of 20717449 is about 274.6494663235.

The spelling of 20717449 in words is "twenty million, seven hundred seventeen thousand, four hundred forty-nine".