1216563624 has 80 divisors (see below), whose sum is σ = 3416810100. Its totient is φ = 404414208.

The previous prime is 1216563577. The next prime is 1216563637. The reversal of 1216563624 is 4263656121.

1216563624 is a `hidden beast` number, since 1 + 2 + 16 + 5 + 636 + 2 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1151244900 + 65318724 = 33930^2 + 8082^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 254892 + ... + 259620.

Almost surely, 2^1216563624 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 1216563624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1708405050).

1216563624 is an abundant number, since it is smaller than the sum of its proper divisors (2200246476).

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

1216563624 is a wasteful number, since it uses less digits than its factorization.

1216563624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5144 (or 5131 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The square root of 1216563624 is about 34879.2721254329. The cubic root of 1216563624 is about 1067.5255435790.

The spelling of 1216563624 in words is "one billion, two hundred sixteen million, five hundred sixty-three thousand, six hundred twenty-four".