1918684847556 has 27 divisors (see below), whose sum is σ = 4850029928653. Its totient is φ = 639558845520.

The previous prime is 1918684847549. The next prime is 1918684847581. The reversal of 1918684847556 is 6557484868191.

It is a happy number.

The square root of 1918684847556 is 1385166.

It is a perfect power (a square), and thus also a powerful number.

1918684847556 is a `hidden beast` number, since 1 + 9 + 1 + 8 + 68 + 4 + 8 + 4 + 7 + 556 = 666.

It can be written as a sum of positive squares in only one way, i.e., 228164807556 + 1690520040000 = 477666^2 + 1300200^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 8195566 + ... + 8426426.

Almost surely, 2^{1918684847556} is an apocalyptic number.

1918684847556 is the 1385166-th square number.

It is an amenable number.

1918684847556 is an abundant number, since it is smaller than the sum of its proper divisors (2931345081097).

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

1918684847556 is an frugal number, since it uses more digits than its factorization.

1918684847556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 461732 (or 230866 counting only the distinct ones).

The product of its digits is 464486400, while the sum is 72.

The spelling of 1918684847556 in words is "one trillion, nine hundred eighteen billion, six hundred eighty-four million, eight hundred forty-seven thousand, five hundred fifty-six".