21213223033 has 4 divisors (see below), whose sum is σ = 22461059700. Its totient is φ = 19965386368.

The previous prime is 21213223007. The next prime is 21213223043. The reversal of 21213223033 is 33032231212.

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 18726006649 + 2487216384 = 136843^2 + 49872^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21213223033 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21213222995 and 21213223013.

It is not an unprimeable number, because it can be changed into a prime (21213223043) 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, 623918308 + ... + 623918341.

It is an arithmetic number, because the mean of its divisors is an integer number (5615264925).

Almost surely, 2^21213223033 is an apocalyptic number.

It is an amenable number.

21213223033 is a deficient number, since it is larger than the sum of its proper divisors (1247836667).

21213223033 is a wasteful number, since it uses less digits than its factorization.

21213223033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1247836666.

The product of its (nonzero) digits is 1296, while the sum is 22.

Adding to 21213223033 its reverse (33032231212), we get a palindrome (54245454245).

The spelling of 21213223033 in words is "twenty-one billion, two hundred thirteen million, two hundred twenty-three thousand, thirty-three".