1218244820 has 144 divisors (see below), whose sum is σ = 3026892288. Its totient is φ = 408913920.

The previous prime is 1218244801. The next prime is 1218244829. The reversal of 1218244820 is 284428121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1218244829) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2329079 + ... + 2329601.

Almost surely, 2^1218244820 is an apocalyptic number.

1218244820 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 1218244820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1513446144).

1218244820 is an abundant number, since it is smaller than the sum of its proper divisors (1808647468).

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

1218244820 is a wasteful number, since it uses less digits than its factorization.

1218244820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 610 (or 591 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 32.

The square root of 1218244820 is about 34903.3640212516. The cubic root of 1218244820 is about 1068.0170629022.

The spelling of 1218244820 in words is "one billion, two hundred eighteen million, two hundred forty-four thousand, eight hundred twenty".