21123202033 has 4 divisors (see below), whose sum is σ = 21851588340. Its totient is φ = 20394815728.

The previous prime is 21123201997. The next prime is 21123202039. The reversal of 21123202033 is 33020232112.

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

It can be written as a sum of positive squares in 2 ways, for example, as 9798624144 + 11324577889 = 98988^2 + 106417^2 .

It is a cyclic number.

It is not a de Polignac number, because 21123202033 - 2⁹ = 21123201521 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 21123202033.

It is not an unprimeable number, because it can be changed into a prime (21123202039) 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, 364193110 + ... + 364193167.

It is an arithmetic number, because the mean of its divisors is an integer number (5462897085).

Almost surely, 2^21123202033 is an apocalyptic number.

It is an amenable number.

21123202033 is a deficient number, since it is larger than the sum of its proper divisors (728386307).

21123202033 is an equidigital number, since it uses as much as digits as its factorization.

21123202033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 728386306.

The product of its (nonzero) digits is 432, while the sum is 19.

Adding to 21123202033 its reverse (33020232112), we get a palindrome (54143434145).

The spelling of 21123202033 in words is "twenty-one billion, one hundred twenty-three million, two hundred two thousand, thirty-three".