21212002121210 has 16 divisors (see below), whose sum is σ = 38238002063496. Its totient is φ = 8472267905088.

The previous prime is 21212002121197. The next prime is 21212002121221. The reversal of 21212002121210 is 1212120021212.

It can be written as a sum of positive squares in 4 ways, for example, as 21176811737929 + 35190383281 = 4601827^2 + 187591^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1566610817 + ... + 1566624356.

Almost surely, 2^{21212002121210} is an apocalyptic number.

21212002121210 is a deficient number, since it is larger than the sum of its proper divisors (17025999942286).

21212002121210 is a wasteful number, since it uses less digits than its factorization.

21212002121210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3133235857.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21212002121210 its reverse (1212120021212), we get a palindrome (22424122142422).

The spelling of 21212002121210 in words is "twenty-one trillion, two hundred twelve billion, two million, one hundred twenty-one thousand, two hundred ten".