221124717121 has 81 divisors (see below), whose sum is σ = 293642082531. Its totient is φ = 165900319200.

The previous prime is 221124717109. The next prime is 221124717131. The reversal of 221124717121 is 121717421122.

The square root of 221124717121 is 470239.

It is a perfect power (a square), and thus also a powerful number.

221124717121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 216657666225 + 4467050896 = 465465^2 + 66836^2 .

It is not a de Polignac number, because 221124717121 - 2¹⁷ = 221124586049 is a prime.

It is a super-2 number, since 2×221124717121² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (221124717101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 1122460395 + ... + 1122460591.

Almost surely, 2^221124717121 is an apocalyptic number.

221124717121 is the 470239-th square number.

221124717121 is the 235120-th centered octagonal number.

It is an amenable number.

221124717121 is a deficient number, since it is larger than the sum of its proper divisors (72517365410).

221124717121 is an equidigital number, since it uses as much as digits as its factorization.

221124717121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 492 (or 246 counting only the distinct ones).

The product of its digits is 3136, while the sum is 31.

Multiplying 221124717121 by its product of digits (3136), we get a square (693447112891456 = 26333384²).

The spelling of 221124717121 in words is "two hundred twenty-one billion, one hundred twenty-four million, seven hundred seventeen thousand, one hundred twenty-one".