1218820554728 has 128 divisors (see below), whose sum is σ = 2753574912000. Its totient is φ = 505033905600.

The previous prime is 1218820554719. The next prime is 1218820554761. The reversal of 1218820554728 is 8274550288121.

It is a self number, because there is not a number n which added to its sum of digits gives 1218820554728.

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, 100964933 + ... + 100977003.

It is an arithmetic number, because the mean of its divisors is an integer number (21512304000).

Almost surely, 2^{1218820554728} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1218820554728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1376787456000).

1218820554728 is an abundant number, since it is smaller than the sum of its proper divisors (1534754357272).

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

1218820554728 is a wasteful number, since it uses less digits than its factorization.

1218820554728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13316 (or 13298 counting only the distinct ones).

The product of its (nonzero) digits is 2867200, while the sum is 53.

The spelling of 1218820554728 in words is "one trillion, two hundred eighteen billion, eight hundred twenty million, five hundred fifty-four thousand, seven hundred twenty-eight".