1216819747644 has 48 divisors (see below), whose sum is σ = 2963765468160. Its totient is φ = 388112123520.

The previous prime is 1216819747601. The next prime is 1216819747673. The reversal of 1216819747644 is 4467479186121.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18343414 + ... + 18409629.

It is an arithmetic number, because the mean of its divisors is an integer number (61745113920).

Almost surely, 2^{1216819747644} is an apocalyptic number.

It is an amenable number.

1216819747644 is an abundant number, since it is smaller than the sum of its proper divisors (1746945720516).

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

1216819747644 is a wasteful number, since it uses less digits than its factorization.

1216819747644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36753170 (or 36753168 counting only the distinct ones).

The product of its digits is 16257024, while the sum is 60.

The spelling of 1216819747644 in words is "one trillion, two hundred sixteen billion, eight hundred nineteen million, seven hundred forty-seven thousand, six hundred forty-four".