221055511 has 2 divisors, whose sum is σ = 221055512. Its totient is φ = 221055510.

The previous prime is 221055491. The next prime is 221055517. The reversal of 221055511 is 115550122.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221055511 - 2⁷ = 221055383 is a prime.

It is a super-2 number, since 2×221055511² = 97731077886942242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221055517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110527755 + 110527756.

It is an arithmetic number, because the mean of its divisors is an integer number (110527756).

Almost surely, 2^221055511 is an apocalyptic number.

221055511 is a deficient number, since it is larger than the sum of its proper divisors (1).

221055511 is an equidigital number, since it uses as much as digits as its factorization.

221055511 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 500, while the sum is 22.

The square root of 221055511 is about 14867.9356670656. The cubic root of 221055511 is about 604.6449762345.

The spelling of 221055511 in words is "two hundred twenty-one million, fifty-five thousand, five hundred eleven".