1218213648 has 160 divisors (see below), whose sum is σ = 3620601600. Its totient is φ = 391910400.

The previous prime is 1218213613. The next prime is 1218213649. The reversal of 1218213648 is 8463128121.

1218213648 is a `hidden beast` number, since 1 + 2 + 1 + 8 + 2 + 1 + 3 + 648 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (1218213649) 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 31 ways as a sum of consecutive naturals, for example, 1930293 + ... + 1930923.

It is an arithmetic number, because the mean of its divisors is an integer number (22628760).

Almost surely, 2^1218213648 is an apocalyptic number.

1218213648 is a gapful number since it is divisible by the number (18) 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 1218213648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1810300800).

1218213648 is an abundant number, since it is smaller than the sum of its proper divisors (2402387952).

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

1218213648 is a wasteful number, since it uses less digits than its factorization.

1218213648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 798 (or 786 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 1218213648 is about 34902.9174711800. The cubic root of 1218213648 is about 1068.0079534820.

The spelling of 1218213648 in words is "one billion, two hundred eighteen million, two hundred thirteen thousand, six hundred forty-eight".