247321 has 4 divisors (see below), whose sum is σ = 249700. Its totient is φ = 244944.

The previous prime is 247309. The next prime is 247337. The reversal of 247321 is 123742.

247321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 123742 = 2 ⋅61871.

It can be written as a sum of positive squares in 2 ways, for example, as 78400 + 168921 = 280^2 + 411^2 .

It is a cyclic number.

It is not a de Polignac number, because 247321 - 2⁷ = 247193 is a prime.

It is a super-2 number, since 2×247321² = 122335354082, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (247301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1026 + ... + 1243.

It is an arithmetic number, because the mean of its divisors is an integer number (62425).

2²⁴⁷³²¹ is an apocalyptic number.

It is an amenable number.

247321 is a deficient number, since it is larger than the sum of its proper divisors (2379).

247321 is a wasteful number, since it uses less digits than its factorization.

247321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2378.

The product of its digits is 336, while the sum is 19.

The square root of 247321 is about 497.3137842449. The cubic root of 247321 is about 62.7702219974.

The spelling of 247321 in words is "two hundred forty-seven thousand, three hundred twenty-one", and thus it is an iban number.