1218873840 has 80 divisors (see below), whose sum is σ = 3787117728. Its totient is φ = 324292608.

The previous prime is 1218873839. The next prime is 1218873853. The reversal of 1218873840 is 483788121.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 1218873792 and 1218873801.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 104124 + ... + 115236.

Almost surely, 2^1218873840 is an apocalyptic number.

1218873840 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 1218873840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1893558864).

1218873840 is an abundant number, since it is smaller than the sum of its proper divisors (2568243888).

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

1218873840 is a wasteful number, since it uses less digits than its factorization.

1218873840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11586 (or 11580 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 42.

The square root of 1218873840 is about 34912.3737376879. The cubic root of 1218873840 is about 1068.2008487582.

The spelling of 1218873840 in words is "one billion, two hundred eighteen million, eight hundred seventy-three thousand, eight hundred forty".