21100203443 has 8 divisors (see below), whose sum is σ = 23019458736. Its totient is φ = 19181124000.

The previous prime is 21100203431. The next prime is 21100203479. The reversal of 21100203443 is 34430200112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21100203443 - 2²⁸ = 20831767987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21100203493) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 418493 + ... + 466193.

It is an arithmetic number, because the mean of its divisors is an integer number (2877432342).

Almost surely, 2^21100203443 is an apocalyptic number.

21100203443 is a deficient number, since it is larger than the sum of its proper divisors (1919255293).

21100203443 is a wasteful number, since it uses less digits than its factorization.

21100203443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87925.

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21100203443 its reverse (34430200112), we get a palindrome (55530403555).

The spelling of 21100203443 in words is "twenty-one billion, one hundred million, two hundred three thousand, four hundred forty-three".