13535541221 has 2 divisors, whose sum is σ = 13535541222. Its totient is φ = 13535541220.

The previous prime is 13535541197. The next prime is 13535541223. The reversal of 13535541221 is 12214553531.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10792924321 + 2742616900 = 103889^2 + 52370^2 .

It is an emirp because it is prime and its reverse (12214553531) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13535541221 - 2²⁶ = 13468432357 is a prime.

It is a super-2 number, since 2×13535541221² (a number of 21 digits) contains 22 as substring.

Together with 13535541223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13535541223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6767770610 + 6767770611.

It is an arithmetic number, because the mean of its divisors is an integer number (6767770611).

Almost surely, 2^13535541221 is an apocalyptic number.

It is an amenable number.

13535541221 is a deficient number, since it is larger than the sum of its proper divisors (1).

13535541221 is an equidigital number, since it uses as much as digits as its factorization.

13535541221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18000, while the sum is 32.

The spelling of 13535541221 in words is "thirteen billion, five hundred thirty-five million, five hundred forty-one thousand, two hundred twenty-one".