243220445 has 32 divisors (see below), whose sum is σ = 339165792. Its totient is φ = 165814272.

The previous prime is 243220421. The next prime is 243220447. The reversal of 243220445 is 544022342.

It is a happy number.

It can be written as a sum of positive squares in 16 ways, for example, as 109286116 + 133934329 = 10454^2 + 11573^2 .

It is not a de Polignac number, because 243220445 - 2⁸ = 243220189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243220447) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 56489 + ... + 60641.

It is an arithmetic number, because the mean of its divisors is an integer number (10598931).

Almost surely, 2^243220445 is an apocalyptic number.

It is an amenable number.

243220445 is a deficient number, since it is larger than the sum of its proper divisors (95945347).

243220445 is a wasteful number, since it uses less digits than its factorization.

243220445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4241.

The product of its (nonzero) digits is 7680, while the sum is 26.

The square root of 243220445 is about 15595.5264418999. The cubic root of 243220445 is about 624.2137911491.

Adding to 243220445 its reverse (544022342), we get a palindrome (787242787).

The spelling of 243220445 in words is "two hundred forty-three million, two hundred twenty thousand, four hundred forty-five".