212021121 has 32 divisors (see below), whose sum is σ = 316546048. Its totient is φ = 125349120.

The previous prime is 212021113. The next prime is 212021141. The reversal of 212021121 is 121120212.

It is not a de Polignac number, because 212021121 - 2³ = 212021113 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 212021097 and 212021106.

It is not an unprimeable number, because it can be changed into a prime (212021141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 189255 + ... + 190371.

It is an arithmetic number, because the mean of its divisors is an integer number (9892064).

Almost surely, 2^212021121 is an apocalyptic number.

It is an amenable number.

212021121 is a deficient number, since it is larger than the sum of its proper divisors (104524927).

212021121 is a wasteful number, since it uses less digits than its factorization.

212021121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1321.

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 212021121 is about 14560.9450586148. The cubic root of 212021121 is about 596.2929968246.

Adding to 212021121 its reverse (121120212), we get a palindrome (333141333).

Subtracting from 212021121 its reverse (121120212), we obtain a palindrome (90900909).

The spelling of 212021121 in words is "two hundred twelve million, twenty-one thousand, one hundred twenty-one".