321085561 has 4 divisors (see below), whose sum is σ = 321222132. Its totient is φ = 320948992.

The previous prime is 321085559. The next prime is 321085571. The reversal of 321085561 is 165580123.

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 147768336 + 173317225 = 12156^2 + 13165^2 .

It is a cyclic number.

It is not a de Polignac number, because 321085561 - 2¹ = 321085559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (321085571) 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, 64696 + ... + 69481.

It is an arithmetic number, because the mean of its divisors is an integer number (80305533).

Almost surely, 2^321085561 is an apocalyptic number.

It is an amenable number.

321085561 is a deficient number, since it is larger than the sum of its proper divisors (136571).

321085561 is a wasteful number, since it uses less digits than its factorization.

321085561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136570.

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 321085561 is about 17918.8604827428. The cubic root of 321085561 is about 684.7629570349.

The spelling of 321085561 in words is "three hundred twenty-one million, eighty-five thousand, five hundred sixty-one".