216406320000 has 640 divisors, whose sum is σ = 780687600000. Its totient is φ = 52780032000.

The previous prime is 216406319977. The next prime is 216406320019. The reversal of 216406320000 is 23604612.

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 433679751 + ... + 433680249.

It is an arithmetic number, because the mean of its divisors is an integer number (1219824375).

Almost surely, 2^216406320000 is an apocalyptic number.

216406320000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216406320000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (390343800000).

216406320000 is an abundant number, since it is smaller than the sum of its proper divisors (564281280000).

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

216406320000 is a wasteful number, since it uses less digits than its factorization.

216406320000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 688 (or 661 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 216406320000 its reverse (23604612), we get a palindrome (216429924612).

The spelling of 216406320000 in words is "two hundred sixteen billion, four hundred six million, three hundred twenty thousand".