2121212121210 has 576 divisors, whose sum is σ = 7166802543264. Its totient is φ = 431101440000.

The previous prime is 2121212121181. The next prime is 2121212121233. The reversal of 2121212121210 is 121212121212.

2121212121210 is a `hidden beast` number, since 2 + 121 + 212 + 121 + 210 = 666.

2121212121210 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It can be written as a sum of positive squares in 16 ways, for example, as 1381445271801 + 739766849409 = 1175349^2 + 860097^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an alternating number because its digits alternate between even and odd.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 214237260 + ... + 214247160.

Almost surely, 2^{2121212121210} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2121212121210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3583401271632).

2121212121210 is an abundant number, since it is smaller than the sum of its proper divisors (5045590422054).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2121212121210 is a wasteful number, since it uses less digits than its factorization.

2121212121210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10079 (or 10069 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 2121212121210 its reverse (121212121212), we get a palindrome (2242424242422).

It can be divided in two parts, 2121212 and 121210, that added together give a palindrome (2242422).

The spelling of 2121212121210 in words is "two trillion, one hundred twenty-one billion, two hundred twelve million, one hundred twenty-one thousand, two hundred ten".