221211111553 has 2 divisors, whose sum is σ = 221211111554. Its totient is φ = 221211111552.

The previous prime is 221211111487. The next prime is 221211111557. The reversal of 221211111553 is 355111112122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 130214165904 + 90996945649 = 360852^2 + 301657^2 .

It is a cyclic number.

It is not a de Polignac number, because 221211111553 - 2¹³ = 221211103361 is a prime.

It is not a weakly prime, because it can be changed into another prime (221211111557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110605555776 + 110605555777.

It is an arithmetic number, because the mean of its divisors is an integer number (110605555777).

Almost surely, 2^221211111553 is an apocalyptic number.

It is an amenable number.

221211111553 is a deficient number, since it is larger than the sum of its proper divisors (1).

221211111553 is an equidigital number, since it uses as much as digits as its factorization.

221211111553 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 600, while the sum is 25.

Adding to 221211111553 its reverse (355111112122), we get a palindrome (576322223675).

The spelling of 221211111553 in words is "two hundred twenty-one billion, two hundred eleven million, one hundred eleven thousand, five hundred fifty-three".