1218917860 has 48 divisors (see below), whose sum is σ = 2634831360. Its totient is φ = 473466240.

The previous prime is 1218917857. The next prime is 1218917891. The reversal of 1218917860 is 687198121.

It is a happy number.

1218917860 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 90057 + ... + 102703.

It is an arithmetic number, because the mean of its divisors is an integer number (54892320).

Almost surely, 2^1218917860 is an apocalyptic number.

1218917860 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1218917860 is an abundant number, since it is smaller than the sum of its proper divisors (1415913500).

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

1218917860 is a wasteful number, since it uses less digits than its factorization.

1218917860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12796 (or 12794 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 43.

The square root of 1218917860 is about 34913.0041675018. The cubic root of 1218917860 is about 1068.2137080697.

The spelling of 1218917860 in words is "one billion, two hundred eighteen million, nine hundred seventeen thousand, eight hundred sixty".