212121011010121 has 4 divisors (see below), whose sum is σ = 218963624268544. Its totient is φ = 205278397751700.

The previous prime is 212121011009951. The next prime is 212121011010157. The reversal of 212121011010121 is 121010110121212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 212121011010121 - 2¹⁹ = 212121010485833 is a prime.

It is a super-3 number, since 3×212121011010121³ (a number of 44 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212121011010095 and 212121011010104.

It is not an unprimeable number, because it can be changed into a prime (212121011070121) 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, 3421306629165 + ... + 3421306629226.

It is an arithmetic number, because the mean of its divisors is an integer number (54740906067136).

Almost surely, 2^{212121011010121} is an apocalyptic number.

It is an amenable number.

212121011010121 is a deficient number, since it is larger than the sum of its proper divisors (6842613258423).

212121011010121 is an equidigital number, since it uses as much as digits as its factorization.

212121011010121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6842613258422.

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

Adding to 212121011010121 its reverse (121010110121212), we get a palindrome (333131121131333).

It can be divided in two parts, 21212101 and 1010121, that added together give a palindrome (22222222).

The spelling of 212121011010121 in words is "two hundred twelve trillion, one hundred twenty-one billion, eleven million, ten thousand, one hundred twenty-one".