201212221021 has 8 divisors (see below), whose sum is σ = 237886369920. Its totient is φ = 166520458608.

The previous prime is 201212221003. The next prime is 201212221031. The reversal of 201212221021 is 120122212102.

It is a happy number.

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

It is not a de Polignac number, because 201212221021 - 2⁹ = 201212220509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201212220986 and 201212221004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201212221031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 495596401 + ... + 495596806.

It is an arithmetic number, because the mean of its divisors is an integer number (29735796240).

Almost surely, 2^201212221021 is an apocalyptic number.

It is an amenable number.

201212221021 is a deficient number, since it is larger than the sum of its proper divisors (36674148899).

201212221021 is an equidigital number, since it uses as much as digits as its factorization.

201212221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 991193243.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 201212221021 its reverse (120122212102), we get a palindrome (321334433123).

The spelling of 201212221021 in words is "two hundred one billion, two hundred twelve million, two hundred twenty-one thousand, twenty-one".