7712212221221 has 4 divisors (see below), whose sum is σ = 7712221663212. Its totient is φ = 7712202779232.

The previous prime is 7712212221209. The next prime is 7712212221283. The reversal of 7712212221221 is 1221222122177.

It is a happy number.

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 7467315904321 + 244896316900 = 2732639^2 + 494870^2 .

It is a cyclic number.

It is not a de Polignac number, because 7712212221221 - 2¹⁰ = 7712212220197 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 (7712212221421) 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, 3366200 + ... + 5172593.

It is an arithmetic number, because the mean of its divisors is an integer number (1928055415803).

Almost surely, 2^{7712212221221} is an apocalyptic number.

It is an amenable number.

7712212221221 is a deficient number, since it is larger than the sum of its proper divisors (9441991).

7712212221221 is an equidigital number, since it uses as much as digits as its factorization.

7712212221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9441990.

The product of its digits is 6272, while the sum is 32.

Adding to 7712212221221 its reverse (1221222122177), we get a palindrome (8933434343398).

The spelling of 7712212221221 in words is "seven trillion, seven hundred twelve billion, two hundred twelve million, two hundred twenty-one thousand, two hundred twenty-one".