212021023221 has 24 divisors (see below), whose sum is σ = 350884619904. Its totient is φ = 120849680160.

The previous prime is 212021023217. The next prime is 212021023223. The reversal of 212021023221 is 122320120212.

212021023221 is a `hidden beast` number, since 212 + 0 + 210 + 23 + 221 = 666.

212021023221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 212021023221 - 2² = 212021023217 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 212021023194 and 212021023203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212021023223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4213545 + ... + 4263566.

It is an arithmetic number, because the mean of its divisors is an integer number (14620192496).

Almost surely, 2^212021023221 is an apocalyptic number.

212021023221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

212021023221 is a deficient number, since it is larger than the sum of its proper divisors (138863596683).

212021023221 is a wasteful number, since it uses less digits than its factorization.

212021023221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8477521 (or 8477518 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 212021023221 its reverse (122320120212), we get a palindrome (334341143433).

The spelling of 212021023221 in words is "two hundred twelve billion, twenty-one million, twenty-three thousand, two hundred twenty-one".