20863243 has 4 divisors (see below), whose sum is σ = 20908768. Its totient is φ = 20817720.

The previous prime is 20863229. The next prime is 20863247. The reversal of 20863243 is 34236802.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34236802 = 2 ⋅17118401.

It is a cyclic number.

It is not a de Polignac number, because 20863243 - 2⁹ = 20862731 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20863247) 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 in 3 ways as a sum of consecutive naturals, for example, 22068 + ... + 22993.

It is an arithmetic number, because the mean of its divisors is an integer number (5227192).

Almost surely, 2^20863243 is an apocalyptic number.

20863243 is a deficient number, since it is larger than the sum of its proper divisors (45525).

20863243 is an equidigital number, since it uses as much as digits as its factorization.

20863243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45524.

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 20863243 is about 4567.6299105773. The cubic root of 20863243 is about 275.2922205001.

It can be divided in two parts, 2086 and 3243, that added together give a square (5329 = 73²).

The spelling of 20863243 in words is "twenty million, eight hundred sixty-three thousand, two hundred forty-three".