20056543 has 4 divisors (see below), whose sum is σ = 21599368. Its totient is φ = 18513720.

The previous prime is 20056523. The next prime is 20056559. The reversal of 20056543 is 34565002.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34565002 = 2 ⋅17282501.

It is a cyclic number.

It is not a de Polignac number, because 20056543 - 2⁵ = 20056511 is a prime.

It is a super-2 number, since 2×20056543² = 804529834221698, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20056523) 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, 771393 + ... + 771418.

It is an arithmetic number, because the mean of its divisors is an integer number (5399842).

Almost surely, 2^20056543 is an apocalyptic number.

20056543 is a deficient number, since it is larger than the sum of its proper divisors (1542825).

20056543 is a wasteful number, since it uses less digits than its factorization.

20056543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1542824.

The product of its (nonzero) digits is 3600, while the sum is 25.

The square root of 20056543 is about 4478.4531927888. The cubic root of 20056543 is about 271.6973231658.

The spelling of 20056543 in words is "twenty million, fifty-six thousand, five hundred forty-three".