20420543 has 16 divisors (see below), whose sum is σ = 24394272. Its totient is φ = 16848000.

The previous prime is 20420531. The next prime is 20420557. The reversal of 20420543 is 34502402.

It is not a de Polignac number, because 20420543 - 2⁶ = 20420479 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 (20420503) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7553 + ... + 9893.

It is an arithmetic number, because the mean of its divisors is an integer number (1524642).

Almost surely, 2^20420543 is an apocalyptic number.

20420543 is a deficient number, since it is larger than the sum of its proper divisors (3973729).

20420543 is a wasteful number, since it uses less digits than its factorization.

20420543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2426.

The product of its (nonzero) digits is 960, while the sum is 20.

The square root of 20420543 is about 4518.9094923444. The cubic root of 20420543 is about 273.3311291051.

Adding to 20420543 its reverse (34502402), we get a palindrome (54922945).

The spelling of 20420543 in words is "twenty million, four hundred twenty thousand, five hundred forty-three".