20980543 has 4 divisors (see below), whose sum is σ = 21704040. Its totient is φ = 20257048.

The previous prime is 20980537. The next prime is 20980559. The reversal of 20980543 is 34508902.

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 20980543 - 2⁵ = 20980511 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20980513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 361705 + ... + 361762.

It is an arithmetic number, because the mean of its divisors is an integer number (5426010).

Almost surely, 2^20980543 is an apocalyptic number.

20980543 is a deficient number, since it is larger than the sum of its proper divisors (723497).

20980543 is an equidigital number, since it uses as much as digits as its factorization.

20980543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 723496.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 20980543 is about 4580.4522702458. The cubic root of 20980543 is about 275.8071843445.

The spelling of 20980543 in words is "twenty million, nine hundred eighty thousand, five hundred forty-three".