20782743 has 4 divisors (see below), whose sum is σ = 27710328. Its totient is φ = 13855160.

The previous prime is 20782733. The next prime is 20782747. The reversal of 20782743 is 34728702.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20782743 - 2⁵ = 20782711 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20782747) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3463788 + ... + 3463793.

It is an arithmetic number, because the mean of its divisors is an integer number (6927582).

Almost surely, 2^20782743 is an apocalyptic number.

20782743 is a deficient number, since it is larger than the sum of its proper divisors (6927585).

20782743 is an equidigital number, since it uses as much as digits as its factorization.

20782743 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6927584.

The product of its (nonzero) digits is 18816, while the sum is 33.

The square root of 20782743 is about 4558.8093840388. The cubic root of 20782743 is about 274.9376960783.

The spelling of 20782743 in words is "twenty million, seven hundred eighty-two thousand, seven hundred forty-three".