21033221213 has 8 divisors (see below), whose sum is σ = 21223585656. Its totient is φ = 20842931200.

The previous prime is 21033221189. The next prime is 21033221233. The reversal of 21033221213 is 31212233012.

It can be written as a sum of positive squares in 4 ways, for example, as 1078268569 + 19954952644 = 32837^2 + 141262^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21033221213 - 2²⁸ = 20764785757 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 (21033221233) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 660293 + ... + 691413.

It is an arithmetic number, because the mean of its divisors is an integer number (2652948207).

Almost surely, 2^21033221213 is an apocalyptic number.

It is an amenable number.

21033221213 is a deficient number, since it is larger than the sum of its proper divisors (190364443).

21033221213 is a wasteful number, since it uses less digits than its factorization.

21033221213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37215.

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

Adding to 21033221213 its reverse (31212233012), we get a palindrome (52245454225).

The spelling of 21033221213 in words is "twenty-one billion, thirty-three million, two hundred twenty-one thousand, two hundred thirteen".