1216202635648 has 768 divisors, whose sum is σ = 3457780220160. Its totient is φ = 418455797760.

The previous prime is 1216202635643. The next prime is 1216202635693. The reversal of 1216202635648 is 8465362026121.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1216202635598 and 1216202635607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216202635643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2223404911 + ... + 2223405457.

It is an arithmetic number, because the mean of its divisors is an integer number (4502317995).

Almost surely, 2^{1216202635648} 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 1216202635648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1728890110080).

1216202635648 is an abundant number, since it is smaller than the sum of its proper divisors (2241577584512).

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

1216202635648 is a wasteful number, since it uses less digits than its factorization.

1216202635648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 703 (or 684 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 46.

It can be divided in two parts, 1216202 and 635648, that added together give a triangular number (1851850 = T₁₉₂₄).

The spelling of 1216202635648 in words is "one trillion, two hundred sixteen billion, two hundred two million, six hundred thirty-five thousand, six hundred forty-eight".