221824116725121 has 27 divisors (see below), whose sum is σ = 320856419985283. Its totient is φ = 147678193569840.

The previous prime is 221824116725083. The next prime is 221824116725137. The reversal of 221824116725121 is 121527611428122.

The square root of 221824116725121 is 14893761.

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

221824116725121 is a `hidden beast` number, since 2 + 2 + 1 + 82 + 41 + 16 + 7 + 2 + 512 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 60567135035121 + 161256981690000 = 7782489^2 + 12698700^2 .

It is not a de Polignac number, because 221824116725121 - 2¹¹ = 221824116723073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221824116725171) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 36683330320 + ... + 36683336366.

Almost surely, 2^{221824116725121} is an apocalyptic number.

221824116725121 is the 14893761-st square number.

221824116725121 is the 7446881-st centered octagonal number.

It is an amenable number.

221824116725121 is a deficient number, since it is larger than the sum of its proper divisors (99032303260162).

221824116725121 is an frugal number, since it uses more digits than its factorization.

221824116725121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13742 (or 6871 counting only the distinct ones).

The product of its digits is 215040, while the sum is 45.

The spelling of 221824116725121 in words is "two hundred twenty-one trillion, eight hundred twenty-four billion, one hundred sixteen million, seven hundred twenty-five thousand, one hundred twenty-one".