21212023313 has 4 divisors (see below), whose sum is σ = 22843717428. Its totient is φ = 19580329200.

The previous prime is 21212023297. The next prime is 21212023331. The reversal of 21212023313 is 31332021212.

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 13997729344 + 7214293969 = 118312^2 + 84937^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212023313 - 2⁴ = 21212023297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21212023213) 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, 815847038 + ... + 815847063.

It is an arithmetic number, because the mean of its divisors is an integer number (5710929357).

Almost surely, 2^21212023313 is an apocalyptic number.

It is an amenable number.

21212023313 is a deficient number, since it is larger than the sum of its proper divisors (1631694115).

21212023313 is a wasteful number, since it uses less digits than its factorization.

21212023313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1631694114.

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

Adding to 21212023313 its reverse (31332021212), we get a palindrome (52544044525).

The spelling of 21212023313 in words is "twenty-one billion, two hundred twelve million, twenty-three thousand, three hundred thirteen".