1218752640 has 384 divisors, whose sum is σ = 4865253120. Its totient is φ = 275374080.

The previous prime is 1218752617. The next prime is 1218752641. The reversal of 1218752640 is 462578121.

1218752640 is a `hidden beast` number, since 1 + 2 + 1 + 8 + 7 + 5 + 2 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

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 = 1218752595 and 1218752604.

It is not an unprimeable number, because it can be changed into a prime (1218752641) 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, 6733350 + ... + 6733530.

It is an arithmetic number, because the mean of its divisors is an integer number (12669930).

Almost surely, 2^1218752640 is an apocalyptic number.

1218752640 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 1218752640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2432626560).

1218752640 is an abundant number, since it is smaller than the sum of its proper divisors (3646500480).

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

1218752640 is a wasteful number, since it uses less digits than its factorization.

1218752640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 380 (or 365 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 1218752640 is about 34910.6379202672. The cubic root of 1218752640 is about 1068.1654416936.

The spelling of 1218752640 in words is "one billion, two hundred eighteen million, seven hundred fifty-two thousand, six hundred forty".