243023440 has 80 divisors (see below), whose sum is σ = 620674560. Its totient is φ = 87759360.

The previous prime is 243023399. The next prime is 243023447. The reversal of 243023440 is 44320342.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243023447) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 137281 + ... + 139039.

It is an arithmetic number, because the mean of its divisors is an integer number (7758432).

Almost surely, 2^243023440 is an apocalyptic number.

243023440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 243023440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (310337280).

243023440 is an abundant number, since it is smaller than the sum of its proper divisors (377651120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

243023440 is a wasteful number, since it uses less digits than its factorization.

243023440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1940 (or 1934 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 22.

The square root of 243023440 is about 15589.2090883406. The cubic root of 243023440 is about 624.0452109473.

Adding to 243023440 its reverse (44320342), we get a palindrome (287343782).

The spelling of 243023440 in words is "two hundred forty-three million, twenty-three thousand, four hundred forty".