243311640 has 192 divisors, whose sum is σ = 864712800. Its totient is φ = 54405120.

The previous prime is 243311611. The next prime is 243311681. The reversal of 243311640 is 46113342.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 243311640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 188116 + ... + 189404.

Almost surely, 2^243311640 is an apocalyptic number.

243311640 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 243311640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (432356400).

243311640 is an abundant number, since it is smaller than the sum of its proper divisors (621401160).

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

243311640 is a wasteful number, since it uses less digits than its factorization.

243311640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1338 (or 1323 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 243311640 is about 15598.4499229891. The cubic root of 243311640 is about 624.2917972880.

Adding to 243311640 its reverse (46113342), we get a palindrome (289424982).

It can be divided in two parts, 243311 and 640, that added together give a triangular number (243951 = T₆₉₈).

The spelling of 243311640 in words is "two hundred forty-three million, three hundred eleven thousand, six hundred forty".