21221201213 has 8 divisors (see below), whose sum is σ = 22343966400. Its totient is φ = 20099022048.

The previous prime is 21221201191. The next prime is 21221201231. The reversal of 21221201213 is 31210212212.

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 21221201213 - 2¹² = 21221197117 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21221201191 and 21221201200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221201713) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71168 + ... + 217961.

It is an arithmetic number, because the mean of its divisors is an integer number (2792995800).

Almost surely, 2^21221201213 is an apocalyptic number.

It is an amenable number.

21221201213 is a deficient number, since it is larger than the sum of its proper divisors (1122765187).

21221201213 is a wasteful number, since it uses less digits than its factorization.

21221201213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 293011.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 21221201213 its reverse (31210212212), we get a palindrome (52431413425).

The spelling of 21221201213 in words is "twenty-one billion, two hundred twenty-one million, two hundred one thousand, two hundred thirteen".