20239543 has 4 divisors (see below), whose sum is σ = 20418768. Its totient is φ = 20060320.

The previous prime is 20239529. The next prime is 20239553. The reversal of 20239543 is 34593202.

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 20239543 - 2²¹ = 18142391 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 (20239523) 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, 89443 + ... + 89668.

It is an arithmetic number, because the mean of its divisors is an integer number (5104692).

Almost surely, 2^20239543 is an apocalyptic number.

20239543 is a deficient number, since it is larger than the sum of its proper divisors (179225).

20239543 is a wasteful number, since it uses less digits than its factorization.

20239543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179224.

The product of its (nonzero) digits is 6480, while the sum is 28.

The square root of 20239543 is about 4498.8379610739. The cubic root of 20239543 is about 272.5211632415.

The spelling of 20239543 in words is "twenty million, two hundred thirty-nine thousand, five hundred forty-three".