20713243 has 2 divisors, whose sum is σ = 20713244. Its totient is φ = 20713242.

The previous prime is 20713219. The next prime is 20713261. The reversal of 20713243 is 34231702.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20713243 is a prime.

It is not a weakly prime, because it can be changed into another prime (20716243) 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, 10356621 + 10356622.

It is an arithmetic number, because the mean of its divisors is an integer number (10356622).

Almost surely, 2^20713243 is an apocalyptic number.

20713243 is a deficient number, since it is larger than the sum of its proper divisors (1).

20713243 is an equidigital number, since it uses as much as digits as its factorization.

20713243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 22.

The square root of 20713243 is about 4551.1803963368. The cubic root of 20713243 is about 274.6308788703.

Adding to 20713243 its reverse (34231702), we get a palindrome (54944945).

The spelling of 20713243 in words is "twenty million, seven hundred thirteen thousand, two hundred forty-three".