997982209 has 8 divisors (see below), whose sum is σ = 1162071360. Its totient is φ = 839273136.

The previous prime is 997982179. The next prime is 997982221. The reversal of 997982209 is 902289799.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 997982209 - 2⁷ = 997982081 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 997982209.

It is not an unprimeable number, because it can be changed into a prime (997982299) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 1344619 + ... + 1345360.

It is an arithmetic number, because the mean of its divisors is an integer number (145258920).

It is a Proth number, since it is equal to 3807 ⋅ 2¹⁸ + 1 and 3807 < 2¹⁸.

Almost surely, 2^997982209 is an apocalyptic number.

It is an amenable number.

997982209 is a deficient number, since it is larger than the sum of its proper divisors (164089151).

997982209 is a wasteful number, since it uses less digits than its factorization.

997982209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2690039.

The product of its (nonzero) digits is 1469664, while the sum is 55.

The square root of 997982209 is about 31590.8564144754. The cubic root of 997982209 is about 999.3269501055.

The spelling of 997982209 in words is "nine hundred ninety-seven million, nine hundred eighty-two thousand, two hundred nine".