20743517 has 2 divisors, whose sum is σ = 20743518. Its totient is φ = 20743516.

The previous prime is 20743483. The next prime is 20743531. The reversal of 20743517 is 71534702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15202201 + 5541316 = 3899^2 + 2354^2 .

It is a cyclic number.

It is not a de Polignac number, because 20743517 - 2⁶ = 20743453 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20743517.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20743537) 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, 10371758 + 10371759.

It is an arithmetic number, because the mean of its divisors is an integer number (10371759).

Almost surely, 2^20743517 is an apocalyptic number.

It is an amenable number.

20743517 is a deficient number, since it is larger than the sum of its proper divisors (1).

20743517 is an equidigital number, since it uses as much as digits as its factorization.

20743517 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5880, while the sum is 29.

The square root of 20743517 is about 4554.5051322839. The cubic root of 20743517 is about 274.7646117984.

The spelling of 20743517 in words is "twenty million, seven hundred forty-three thousand, five hundred seventeen".