997321 has 4 divisors (see below), whose sum is σ = 1074052. Its totient is φ = 920592.

The previous prime is 997319. The next prime is 997327. The reversal of 997321 is 123799.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 455625 + 541696 = 675^2 + 736^2 .

It is a cyclic number.

It is not a de Polignac number, because 997321 - 2¹ = 997319 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (997327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38346 + ... + 38371.

It is an arithmetic number, because the mean of its divisors is an integer number (268513).

2⁹⁹⁷³²¹ is an apocalyptic number.

It is an amenable number.

997321 is a deficient number, since it is larger than the sum of its proper divisors (76731).

997321 is a wasteful number, since it uses less digits than its factorization.

997321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76730.

The product of its digits is 3402, while the sum is 31.

The square root of 997321 is about 998.6596016662. The cubic root of 997321 is about 99.9106201362.

The spelling of 997321 in words is "nine hundred ninety-seven thousand, three hundred twenty-one".