243390840 has 384 divisors, whose sum is σ = 957381120. Its totient is φ = 48921600.

The previous prime is 243390811. The next prime is 243390841. The reversal of 243390840 is 48093342.

243390840 is digitally balanced in base 2, 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 (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243390841) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3428005 + ... + 3428075.

It is an arithmetic number, because the mean of its divisors is an integer number (2493180).

Almost surely, 2^243390840 is an apocalyptic number.

243390840 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 243390840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (478690560).

243390840 is an abundant number, since it is smaller than the sum of its proper divisors (713990280).

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

243390840 is a wasteful number, since it uses less digits than its factorization.

243390840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163 (or 152 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 243390840 is about 15600.9884302245. The cubic root of 243390840 is about 624.3595273625.

The spelling of 243390840 in words is "two hundred forty-three million, three hundred ninety thousand, eight hundred forty".