216819916544 has 216 divisors, whose sum is σ = 550110231216. Its totient is φ = 84338688000.

The previous prime is 216819916543. The next prime is 216819916553. The reversal of 216819916544 is 445619918612.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (56).

It is a self number, because there is not a number n which added to its sum of digits gives 216819916544.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216819916543) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 146400284 + ... + 146401764.

It is an arithmetic number, because the mean of its divisors is an integer number (2546806626).

Almost surely, 2^216819916544 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 216819916544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (275055115608).

216819916544 is an abundant number, since it is smaller than the sum of its proper divisors (333290314672).

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

216819916544 is a wasteful number, since it uses less digits than its factorization.

216819916544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2583 (or 2562 counting only the distinct ones).

The product of its digits is 3732480, while the sum is 56.

The spelling of 216819916544 in words is "two hundred sixteen billion, eight hundred nineteen million, nine hundred sixteen thousand, five hundred forty-four".