243571640 has 128 divisors (see below), whose sum is σ = 630504000. Its totient is φ = 83939328.

The previous prime is 243571579. The next prime is 243571663. The reversal of 243571640 is 46175342.

243571640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 243571597 and 243571606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 879182 + ... + 879458.

Almost surely, 2^243571640 is an apocalyptic number.

243571640 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 243571640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (315252000).

243571640 is an abundant number, since it is smaller than the sum of its proper divisors (386932360).

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

243571640 is a wasteful number, since it uses less digits than its factorization.

243571640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409 (or 405 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 32.

The square root of 243571640 is about 15606.7818591790. The cubic root of 243571640 is about 624.5140884552.

The spelling of 243571640 in words is "two hundred forty-three million, five hundred seventy-one thousand, six hundred forty".