212021122121 has 16 divisors (see below), whose sum is σ = 231172558848. Its totient is φ = 193662835200.

The previous prime is 212021122097. The next prime is 212021122129. The reversal of 212021122121 is 121221120212.

It is a cyclic number.

It is not a de Polignac number, because 212021122121 - 2⁶ = 212021122057 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 212021122121.

It is not an unprimeable number, because it can be changed into a prime (212021122129) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 663185 + ... + 929438.

It is an arithmetic number, because the mean of its divisors is an integer number (14448284928).

Almost surely, 2^212021122121 is an apocalyptic number.

It is an amenable number.

212021122121 is a deficient number, since it is larger than the sum of its proper divisors (19151436727).

212021122121 is a wasteful number, since it uses less digits than its factorization.

212021122121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1592872.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 212021122121 its reverse (121221120212), we get a palindrome (333242242333).

The spelling of 212021122121 in words is "two hundred twelve billion, twenty-one million, one hundred twenty-two thousand, one hundred twenty-one".