21201210443 has 4 divisors (see below), whose sum is σ = 24229954800. Its totient is φ = 18172466088.

The previous prime is 21201210397. The next prime is 21201210461. The reversal of 21201210443 is 34401210212.

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

It is not a de Polignac number, because 21201210443 - 2²⁸ = 20932774987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21201210143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1514372168 + ... + 1514372181.

It is an arithmetic number, because the mean of its divisors is an integer number (6057488700).

Almost surely, 2^21201210443 is an apocalyptic number.

21201210443 is a deficient number, since it is larger than the sum of its proper divisors (3028744357).

21201210443 is an equidigital number, since it uses as much as digits as its factorization.

21201210443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3028744356.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21201210443 its reverse (34401210212), we get a palindrome (55602420655).

The spelling of 21201210443 in words is "twenty-one billion, two hundred one million, two hundred ten thousand, four hundred forty-three".