216820908 has 96 divisors (see below), whose sum is σ = 590929920. Its totient is φ = 68618880.

The previous prime is 216820889. The next prime is 216820909. The reversal of 216820908 is 809028612.

It is a super-2 number, since 2×216820908² = 94022612291888928, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (216820909) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 474216 + ... + 474672.

It is an arithmetic number, because the mean of its divisors is an integer number (6155520).

Almost surely, 2^216820908 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 216820908, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (295464960).

216820908 is an abundant number, since it is smaller than the sum of its proper divisors (374109012).

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

216820908 is a wasteful number, since it uses less digits than its factorization.

216820908 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 684 (or 676 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 216820908 is about 14724.8398293496. The cubic root of 216820908 is about 600.7591391079.

The spelling of 216820908 in words is "two hundred sixteen million, eight hundred twenty thousand, nine hundred eight".