21022121221210 has 8 divisors (see below), whose sum is σ = 37839818198196. Its totient is φ = 8408848488480.

The previous prime is 21022121221151. The next prime is 21022121221217. The reversal of 21022121221210 is 1212212122012.

It can be written as a sum of positive squares in 2 ways, for example, as 20387943120601 + 634178100609 = 4515301^2 + 796353^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21022121221217) 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, 1051106061051 + ... + 1051106061070.

Almost surely, 2^{21022121221210} is an apocalyptic number.

21022121221210 is a deficient number, since it is larger than the sum of its proper divisors (16817696976986).

21022121221210 is a wasteful number, since it uses less digits than its factorization.

21022121221210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2102212122128.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21022121221210 its reverse (1212212122012), we get a palindrome (22234333343222).

The spelling of 21022121221210 in words is "twenty-one trillion, twenty-two billion, one hundred twenty-one million, two hundred twenty-one thousand, two hundred ten".