21103312033 has 4 divisors (see below), whose sum is σ = 21552318720. Its totient is φ = 20654305348.

The previous prime is 21103311979. The next prime is 21103312039. The reversal of 21103312033 is 33021330112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21103312033 - 2¹³ = 21103303841 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21103312033.

It is not an unprimeable number, because it can be changed into a prime (21103312039) 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, 224503273 + ... + 224503366.

It is an arithmetic number, because the mean of its divisors is an integer number (5388079680).

Almost surely, 2^21103312033 is an apocalyptic number.

It is an amenable number.

21103312033 is a deficient number, since it is larger than the sum of its proper divisors (449006687).

21103312033 is an equidigital number, since it uses as much as digits as its factorization.

21103312033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 449006686.

The product of its (nonzero) digits is 324, while the sum is 19.

Adding to 21103312033 its reverse (33021330112), we get a palindrome (54124642145).

The spelling of 21103312033 in words is "twenty-one billion, one hundred three million, three hundred twelve thousand, thirty-three".