21323120213 has 4 divisors (see below), whose sum is σ = 22577421420. Its totient is φ = 20068819008.

The previous prime is 21323120183. The next prime is 21323120237. The reversal of 21323120213 is 31202132312.

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 15841494769 + 5481625444 = 125863^2 + 74038^2 .

It is a cyclic number.

It is not a de Polignac number, because 21323120213 - 2⁶ = 21323120149 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 (21323120713) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 627150578 + ... + 627150611.

It is an arithmetic number, because the mean of its divisors is an integer number (5644355355).

Almost surely, 2^21323120213 is an apocalyptic number.

It is an amenable number.

21323120213 is a deficient number, since it is larger than the sum of its proper divisors (1254301207).

21323120213 is a wasteful number, since it uses less digits than its factorization.

21323120213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1254301206.

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

Adding to 21323120213 its reverse (31202132312), we get a palindrome (52525252525).

The spelling of 21323120213 in words is "twenty-one billion, three hundred twenty-three million, one hundred twenty thousand, two hundred thirteen".