21001223012303 has 4 divisors (see below), whose sum is σ = 21001232268888. Its totient is φ = 21001213755720.

The previous prime is 21001223012291. The next prime is 21001223012369. The reversal of 21001223012303 is 30321032210012.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21001223012303 - 2³⁸ = 20726345105359 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 (21001213012303) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1342193 + ... + 6618453.

It is an arithmetic number, because the mean of its divisors is an integer number (5250308067222).

Almost surely, 2^{21001223012303} is an apocalyptic number.

21001223012303 is a deficient number, since it is larger than the sum of its proper divisors (9256585).

21001223012303 is an equidigital number, since it uses as much as digits as its factorization.

21001223012303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9256584.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 21001223012303 its reverse (30321032210012), we get a palindrome (51322255222315).

The spelling of 21001223012303 in words is "twenty-one trillion, one billion, two hundred twenty-three million, twelve thousand, three hundred three".