221340145 has 24 divisors (see below), whose sum is σ = 289555776. Its totient is φ = 162347328.

The previous prime is 221340143. The next prime is 221340149. The reversal of 221340145 is 541043122.

221340145 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221340145 - 2¹ = 221340143 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221340143) 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, 136932 + ... + 138538.

It is an arithmetic number, because the mean of its divisors is an integer number (12064824).

Almost surely, 2^221340145 is an apocalyptic number.

It is an amenable number.

221340145 is a deficient number, since it is larger than the sum of its proper divisors (68215631).

221340145 is a wasteful number, since it uses less digits than its factorization.

221340145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1801 (or 1788 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 221340145 is about 14877.5046630811. The cubic root of 221340145 is about 604.9043812184.

Adding to 221340145 its reverse (541043122), we get a palindrome (762383267).

The spelling of 221340145 in words is "two hundred twenty-one million, three hundred forty thousand, one hundred forty-five".