321099997 has 2 divisors, whose sum is σ = 321099998. Its totient is φ = 321099996.

The previous prime is 321099991. The next prime is 321100001. The reversal of 321099997 is 799990123.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 175801081 + 145298916 = 13259^2 + 12054^2 .

It is a cyclic number.

It is not a de Polignac number, because 321099997 - 2¹⁹ = 320575709 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 321099997.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (321099991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160549998 + 160549999.

It is an arithmetic number, because the mean of its divisors is an integer number (160549999).

Almost surely, 2^321099997 is an apocalyptic number.

It is an amenable number.

321099997 is a deficient number, since it is larger than the sum of its proper divisors (1).

321099997 is an equidigital number, since it uses as much as digits as its factorization.

321099997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 275562, while the sum is 49.

The square root of 321099997 is about 17919.2632940085. The cubic root of 321099997 is about 684.7732191905.

The spelling of 321099997 in words is "three hundred twenty-one million, ninety-nine thousand, nine hundred ninety-seven".