221592161 has 24 divisors (see below), whose sum is σ = 282375720. Its totient is φ = 172580352.

The previous prime is 221592139. The next prime is 221592187. The reversal of 221592161 is 161295122.

221592161 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 4 ways, for example, as 12645136 + 208947025 = 3556^2 + 14455^2 .

It is not a de Polignac number, because 221592161 - 2¹⁰ = 221591137 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221592121) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19571 + ... + 28743.

It is an arithmetic number, because the mean of its divisors is an integer number (11765655).

Almost surely, 2^221592161 is an apocalyptic number.

It is an amenable number.

221592161 is a deficient number, since it is larger than the sum of its proper divisors (60783559).

221592161 is a wasteful number, since it uses less digits than its factorization.

221592161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9233 (or 9226 counting only the distinct ones).

The product of its digits is 2160, while the sum is 29.

The square root of 221592161 is about 14885.9719534869. The cubic root of 221592161 is about 605.1338737963.

The spelling of 221592161 in words is "two hundred twenty-one million, five hundred ninety-two thousand, one hundred sixty-one".