212121331330021 has 4 divisors (see below), whose sum is σ = 218963954921344. Its totient is φ = 205278707738700.

The previous prime is 212121331329917. The next prime is 212121331330031. The reversal of 212121331330021 is 120033133121212.

212121331330021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 212121331330021 - 2¹³ = 212121331321829 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212121331330031) 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, 3421311795615 + ... + 3421311795676.

It is an arithmetic number, because the mean of its divisors is an integer number (54740988730336).

Almost surely, 2^{212121331330021} is an apocalyptic number.

It is an amenable number.

212121331330021 is a deficient number, since it is larger than the sum of its proper divisors (6842623591323).

212121331330021 is an equidigital number, since it uses as much as digits as its factorization.

212121331330021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6842623591322.

The product of its (nonzero) digits is 1296, while the sum is 25.

Adding to 212121331330021 its reverse (120033133121212), we get a palindrome (332154464451233).

The spelling of 212121331330021 in words is "two hundred twelve trillion, one hundred twenty-one billion, three hundred thirty-one million, three hundred thirty thousand, twenty-one".