1218640320 has 168 divisors, whose sum is σ = 4336450560. Its totient is φ = 313743360.

The previous prime is 1218640309. The next prime is 1218640327. The reversal of 1218640320 is 230468121.

1218640320 is a `hidden beast` number, since 1 + 2 + 18 + 640 + 3 + 2 + 0 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1218640327) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 76225 + ... + 90815.

Almost surely, 2^1218640320 is an apocalyptic number.

1218640320 is a gapful number since it is divisible by the number (10) 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 1218640320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2168225280).

1218640320 is an abundant number, since it is smaller than the sum of its proper divisors (3117810240).

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

1218640320 is a wasteful number, since it uses less digits than its factorization.

1218640320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14643 (or 14630 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 1218640320 is about 34909.0292044909. The cubic root of 1218640320 is about 1068.1326267142.

The spelling of 1218640320 in words is "one billion, two hundred eighteen million, six hundred forty thousand, three hundred twenty".