216990778368 has 880 divisors, whose sum is σ = 760327461376. Its totient is φ = 54623600640.

The previous prime is 216990778349. The next prime is 216990778393. The reversal of 216990778368 is 863877099612.

It is a junction number, because it is equal to n+sod(n) for n = 216990778299 and 216990778308.

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 79 ways as a sum of consecutive naturals, for example, 2972476380 + ... + 2972476452.

Almost surely, 2^216990778368 is an apocalyptic number.

216990778368 is a gapful number since it is divisible by the number (28) 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 216990778368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (380163730688).

216990778368 is an abundant number, since it is smaller than the sum of its proper divisors (543336683008).

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

216990778368 is an equidigital number, since it uses as much as digits as its factorization.

216990778368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168 (or 129 counting only the distinct ones).

The product of its (nonzero) digits is 54867456, while the sum is 66.

The spelling of 216990778368 in words is "two hundred sixteen billion, nine hundred ninety million, seven hundred seventy-eight thousand, three hundred sixty-eight".