243640505405 has 16 divisors (see below), whose sum is σ = 335734286400. Its totient is φ = 167867141760.

The previous prime is 243640505399. The next prime is 243640505411. The reversal of 243640505405 is 504505046342.

243640505405 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (243640505399) and next prime (243640505411).

It is not a de Polignac number, because 243640505405 - 2⁶ = 243640505341 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 116573360 + ... + 116575449.

It is an arithmetic number, because the mean of its divisors is an integer number (20983392900).

Almost surely, 2^243640505405 is an apocalyptic number.

It is an amenable number.

243640505405 is a deficient number, since it is larger than the sum of its proper divisors (92093780995).

243640505405 is a wasteful number, since it uses less digits than its factorization.

243640505405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233148844.

The product of its (nonzero) digits is 288000, while the sum is 38.

The spelling of 243640505405 in words is "two hundred forty-three billion, six hundred forty million, five hundred five thousand, four hundred five".