20533135243 has 4 divisors (see below), whose sum is σ = 20542975920. Its totient is φ = 20523294568.

The previous prime is 20533135229. The next prime is 20533135247. The reversal of 20533135243 is 34253133502.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20533135243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20533135247) 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, 4917208 + ... + 4921381.

It is an arithmetic number, because the mean of its divisors is an integer number (5135743980).

Almost surely, 2^20533135243 is an apocalyptic number.

20533135243 is a deficient number, since it is larger than the sum of its proper divisors (9840677).

20533135243 is an equidigital number, since it uses as much as digits as its factorization.

20533135243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9840676.

The product of its (nonzero) digits is 32400, while the sum is 31.

Adding to 20533135243 its reverse (34253133502), we get a palindrome (54786268745).

The spelling of 20533135243 in words is "twenty billion, five hundred thirty-three million, one hundred thirty-five thousand, two hundred forty-three".