21212103121210 has 16 divisors (see below), whose sum is σ = 39113048682792. Its totient is φ = 8277893900800.

The previous prime is 21212103121193. The next prime is 21212103121309. The reversal of 21212103121210 is 1212130121212.

It can be written as a sum of positive squares in 4 ways, for example, as 6450670393489 + 14761432727721 = 2539817^2 + 3842061^2 .

It is a super-3 number, since 3×21212103121210³ (a number of 41 digits) contains 333 as substring.

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, 25868418031 + ... + 25868418850.

Almost surely, 2^{21212103121210} is an apocalyptic number.

21212103121210 is a deficient number, since it is larger than the sum of its proper divisors (17900945561582).

21212103121210 is a wasteful number, since it uses less digits than its factorization.

21212103121210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51736836929.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 21212103121210 its reverse (1212130121212), we get a palindrome (22424233242422).

The spelling of 21212103121210 in words is "twenty-one trillion, two hundred twelve billion, one hundred three million, one hundred twenty-one thousand, two hundred ten".