1218236544 has 256 divisors, whose sum is σ = 4223289600. Its totient is φ = 338411520.

The previous prime is 1218236491. The next prime is 1218236557. The reversal of 1218236544 is 4456328121.

It is a happy number.

1218236544 is a `hidden beast` number, since 1 + 2 + 1 + 82 + 36 + 544 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 1218236499 and 1218236508.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 894424 + ... + 895784.

It is an arithmetic number, because the mean of its divisors is an integer number (16497225).

Almost surely, 2^1218236544 is an apocalyptic number.

1218236544 is a gapful number since it is divisible by the number (14) 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 1218236544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2111644800).

1218236544 is an abundant number, since it is smaller than the sum of its proper divisors (3005053056).

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

1218236544 is a wasteful number, since it uses less digits than its factorization.

1218236544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1428 (or 1410 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The square root of 1218236544 is about 34903.2454651426. The cubic root of 1218236544 is about 1068.0146444148.

The spelling of 1218236544 in words is "one billion, two hundred eighteen million, two hundred thirty-six thousand, five hundred forty-four".