11155214221 has 2 divisors, whose sum is σ = 11155214222. Its totient is φ = 11155214220.

The previous prime is 11155214219. The next prime is 11155214263. The reversal of 11155214221 is 12241255111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7675512100 + 3479702121 = 87610^2 + 58989^2 .

It is a cyclic number.

It is not a de Polignac number, because 11155214221 - 2¹ = 11155214219 is a prime.

Together with 11155214219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11155214281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5577607110 + 5577607111.

It is an arithmetic number, because the mean of its divisors is an integer number (5577607111).

Almost surely, 2^11155214221 is an apocalyptic number.

It is an amenable number.

11155214221 is a deficient number, since it is larger than the sum of its proper divisors (1).

11155214221 is an equidigital number, since it uses as much as digits as its factorization.

11155214221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 800, while the sum is 25.

Adding to 11155214221 its reverse (12241255111), we get a palindrome (23396469332).

The spelling of 11155214221 in words is "eleven billion, one hundred fifty-five million, two hundred fourteen thousand, two hundred twenty-one".