20213543 has 4 divisors (see below), whose sum is σ = 23101200. Its totient is φ = 17325888.

The previous prime is 20213503. The next prime is 20213563. The reversal of 20213543 is 34531202.

It is a happy number.

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 20213543 - 2¹⁴ = 20197159 is a prime.

It is a super-2 number, since 2×20213543² = 817174641225698, 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 (20213503) 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, 1443818 + ... + 1443831.

It is an arithmetic number, because the mean of its divisors is an integer number (5775300).

Almost surely, 2^20213543 is an apocalyptic number.

20213543 is a deficient number, since it is larger than the sum of its proper divisors (2887657).

20213543 is an equidigital number, since it uses as much as digits as its factorization.

20213543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2887656.

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 20213543 is about 4495.9473973791. The cubic root of 20213543 is about 272.4044184039.

Adding to 20213543 its reverse (34531202), we get a palindrome (54744745).

The spelling of 20213543 in words is "twenty million, two hundred thirteen thousand, five hundred forty-three".