243216540 has 288 divisors, whose sum is σ = 907683840. Its totient is φ = 52939008.

The previous prime is 243216529. The next prime is 243216583. The reversal of 243216540 is 45612342.

243216540 is a `hidden beast` number, since 2 + 4 + 3 + 2 + 1 + 654 + 0 = 666.

243216540 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 5174797 + ... + 5174843.

It is an arithmetic number, because the mean of its divisors is an integer number (3151680).

Almost surely, 2^243216540 is an apocalyptic number.

243216540 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 243216540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (453841920).

243216540 is an abundant number, since it is smaller than the sum of its proper divisors (664467300).

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

243216540 is a wasteful number, since it uses less digits than its factorization.

243216540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146 (or 101 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 243216540 is about 15595.4012452389. The cubic root of 243216540 is about 624.2104504651.

Adding to 243216540 its reverse (45612342), we get a palindrome (288828882).

The spelling of 243216540 in words is "two hundred forty-three million, two hundred sixteen thousand, five hundred forty".