10021212221 has 4 divisors (see below), whose sum is σ = 10254263712. Its totient is φ = 9788160732.

The previous prime is 10021212211. The next prime is 10021212259. The reversal of 10021212221 is 12221212001.

10021212221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 10021212221 - 2¹⁰ = 10021211197 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 10021212196 and 10021212205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10021212211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 116525681 + ... + 116525766.

It is an arithmetic number, because the mean of its divisors is an integer number (2563565928).

Almost surely, 2^10021212221 is an apocalyptic number.

It is an amenable number.

10021212221 is a deficient number, since it is larger than the sum of its proper divisors (233051491).

10021212221 is an equidigital number, since it uses as much as digits as its factorization.

10021212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233051490.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 10021212221 its reverse (12221212001), we get a palindrome (22242424222).

The spelling of 10021212221 in words is "ten billion, twenty-one million, two hundred twelve thousand, two hundred twenty-one".