201212110220021 has 4 divisors (see below), whose sum is σ = 203058092882700. Its totient is φ = 199366127557344.

The previous prime is 201212110219979. The next prime is 201212110220057. The reversal of 201212110220021 is 120022011212102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 177032870836900 + 24179239383121 = 13305370^2 + 4917239^2 .

It is a cyclic number.

It is not a de Polignac number, because 201212110220021 - 2³⁴ = 201194930350837 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201212110222021) 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 3 ways as a sum of consecutive naturals, for example, 922991331176 + ... + 922991331393.

It is an arithmetic number, because the mean of its divisors is an integer number (50764523220675).

Almost surely, 2^{201212110220021} is an apocalyptic number.

It is an amenable number.

201212110220021 is a deficient number, since it is larger than the sum of its proper divisors (1845982662679).

201212110220021 is a wasteful number, since it uses less digits than its factorization.

201212110220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1845982662678.

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

Adding to 201212110220021 its reverse (120022011212102), we get a palindrome (321234121432123).

The spelling of 201212110220021 in words is "two hundred one trillion, two hundred twelve billion, one hundred ten million, two hundred twenty thousand, twenty-one".