206455321 has 4 divisors (see below), whose sum is σ = 213574500. Its totient is φ = 199336144.

The previous prime is 206455313. The next prime is 206455331. The reversal of 206455321 is 123554602.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 123554602 = 2 ⋅61777301.

It can be written as a sum of positive squares in 2 ways, for example, as 145443600 + 61011721 = 12060^2 + 7811^2 .

It is a cyclic number.

It is not a de Polignac number, because 206455321 - 2³ = 206455313 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 206455321.

It is not an unprimeable number, because it can be changed into a prime (206455331) 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 3 ways as a sum of consecutive naturals, for example, 3559546 + ... + 3559603.

It is an arithmetic number, because the mean of its divisors is an integer number (53393625).

Almost surely, 2^206455321 is an apocalyptic number.

It is an amenable number.

206455321 is a deficient number, since it is larger than the sum of its proper divisors (7119179).

206455321 is an equidigital number, since it uses as much as digits as its factorization.

206455321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7119178.

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 206455321 is about 14368.5531978693. The cubic root of 206455321 is about 591.0288674186.

The spelling of 206455321 in words is "two hundred six million, four hundred fifty-five thousand, three hundred twenty-one".