21212110102210 has 16 divisors (see below), whose sum is σ = 39498411915000. Its totient is φ = 8192263211776.

The previous prime is 21212110102199. The next prime is 21212110102213. The reversal of 21212110102210 is 1220101121212.

It can be written as a sum of positive squares in 4 ways, for example, as 10032669818721 + 11179440283489 = 3167439^2 + 3343567^2 .

It is a super-3 number, since 3×21212110102210³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (21212110102213) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36572603335 + ... + 36572603914.

Almost surely, 2^{21212110102210} is an apocalyptic number.

21212110102210 is a deficient number, since it is larger than the sum of its proper divisors (18286301812790).

21212110102210 is a wasteful number, since it uses less digits than its factorization.

21212110102210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73145207285.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21212110102210 its reverse (1220101121212), we get a palindrome (22432211223422).

The spelling of 21212110102210 in words is "twenty-one trillion, two hundred twelve billion, one hundred ten million, one hundred two thousand, two hundred ten".