243974640 has 160 divisors (see below), whose sum is σ = 930940416. Its totient is φ = 51471360.

The previous prime is 243974623. The next prime is 243974677. The reversal of 243974640 is 46479342.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16255 + ... + 27425.

Almost surely, 2^243974640 is an apocalyptic number.

243974640 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 243974640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (465470208).

243974640 is an abundant number, since it is smaller than the sum of its proper divisors (686965776).

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

243974640 is a wasteful number, since it uses less digits than its factorization.

243974640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11207 (or 11201 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 39.

The square root of 243974640 is about 15619.6875769011. The cubic root of 243974640 is about 624.8583273553.

The spelling of 243974640 in words is "two hundred forty-three million, nine hundred seventy-four thousand, six hundred forty".