212121323021 has 8 divisors (see below), whose sum is σ = 224622646080. Its totient is φ = 199753704288.

The previous prime is 212121323017. The next prime is 212121323027. The reversal of 212121323021 is 120323121212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 212121323021 - 2² = 212121323017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 212121322984 and 212121323002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212121323027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33422816 + ... + 33429161.

It is an arithmetic number, because the mean of its divisors is an integer number (28077830760).

Almost surely, 2^212121323021 is an apocalyptic number.

It is an amenable number.

212121323021 is a deficient number, since it is larger than the sum of its proper divisors (12501323059).

212121323021 is a wasteful number, since it uses less digits than its factorization.

212121323021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66852163.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 212121323021 its reverse (120323121212), we get a palindrome (332444444233).

The spelling of 212121323021 in words is "two hundred twelve billion, one hundred twenty-one million, three hundred twenty-three thousand, twenty-one".