1321982208 has 216 divisors, whose sum is σ = 4017686400. Its totient is φ = 433465344.

The previous prime is 1321982191. The next prime is 1321982219. The reversal of 1321982208 is 8022891231.

It is a tau number, because it is divible by the number of its divisors (216).

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4914298 + ... + 4914566.

It is an arithmetic number, because the mean of its divisors is an integer number (18600400).

Almost surely, 2^1321982208 is an apocalyptic number.

1321982208 is a gapful number since it is divisible by the number (18) 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 1321982208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2008843200).

1321982208 is an abundant number, since it is smaller than the sum of its proper divisors (2695704192).

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

1321982208 is an frugal number, since it uses more digits than its factorization.

1321982208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 379 (or 353 counting only the distinct ones).

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

The square root of 1321982208 is about 36359.0732555163. The cubic root of 1321982208 is about 1097.5101281576.

The spelling of 1321982208 in words is "one billion, three hundred twenty-one million, nine hundred eighty-two thousand, two hundred eight".