243640789 has 8 divisors (see below), whose sum is σ = 284129600. Its totient is φ = 208834668.

The previous prime is 243640723. The next prime is 243640799. The reversal of 243640789 is 987046342.

It is not a de Polignac number, because 243640789 - 2¹⁵ = 243608021 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 (243640799) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 354819 + ... + 355504.

It is an arithmetic number, because the mean of its divisors is an integer number (35516200).

Almost surely, 2^243640789 is an apocalyptic number.

It is an amenable number.

243640789 is a deficient number, since it is larger than the sum of its proper divisors (40488811).

243640789 is an frugal number, since it uses more digits than its factorization.

243640789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 710344 (or 710330 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 43.

The square root of 243640789 is about 15608.9970529820. The cubic root of 243640789 is about 624.5731818684.

The spelling of 243640789 in words is "two hundred forty-three million, six hundred forty thousand, seven hundred eighty-nine".