202712216521 has 2 divisors, whose sum is σ = 202712216522. Its totient is φ = 202712216520.

The previous prime is 202712216519. The next prime is 202712216543. The reversal of 202712216521 is 125612217202.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 170126551296 + 32585665225 = 412464^2 + 180515^2 .

It is a cyclic number.

It is not a de Polignac number, because 202712216521 - 2¹ = 202712216519 is a prime.

Together with 202712216519, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (202712216621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101356108260 + 101356108261.

It is an arithmetic number, because the mean of its divisors is an integer number (101356108261).

Almost surely, 2^202712216521 is an apocalyptic number.

It is an amenable number.

202712216521 is a deficient number, since it is larger than the sum of its proper divisors (1).

202712216521 is an equidigital number, since it uses as much as digits as its factorization.

202712216521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6720, while the sum is 31.

The spelling of 202712216521 in words is "two hundred two billion, seven hundred twelve million, two hundred sixteen thousand, five hundred twenty-one".