20421100503143 has 4 divisors (see below), whose sum is σ = 20619363614928. Its totient is φ = 20222837391360.

The previous prime is 20421100503131. The next prime is 20421100503191. The reversal of 20421100503143 is 34130500112402.

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 20421100503143 - 2³⁰ = 20420026761319 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 (20421100508143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99131555738 + ... + 99131555943.

It is an arithmetic number, because the mean of its divisors is an integer number (5154840903732).

Almost surely, 2^{20421100503143} is an apocalyptic number.

20421100503143 is a deficient number, since it is larger than the sum of its proper divisors (198263111785).

20421100503143 is a wasteful number, since it uses less digits than its factorization.

20421100503143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198263111784.

The product of its (nonzero) digits is 2880, while the sum is 26.

Adding to 20421100503143 its reverse (34130500112402), we get a palindrome (54551600615545).

The spelling of 20421100503143 in words is "twenty trillion, four hundred twenty-one billion, one hundred million, five hundred three thousand, one hundred forty-three".