247813 has 2 divisors, whose sum is σ = 247814. Its totient is φ = 247812.

The previous prime is 247811. The next prime is 247829. The reversal of 247813 is 318742.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 146689 + 101124 = 383^2 + 318^2 .

It is a cyclic number.

It is not a de Polignac number, because 247813 - 2¹ = 247811 is a prime.

It is a super-2 number, since 2×247813² = 122822565938, which contains 22 as substring.

Together with 247811, it forms a pair of twin primes.

247813 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (247811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123906 + 123907.

It is an arithmetic number, because the mean of its divisors is an integer number (123907).

2²⁴⁷⁸¹³ is an apocalyptic number.

It is an amenable number.

247813 is a deficient number, since it is larger than the sum of its proper divisors (1).

247813 is an equidigital number, since it uses as much as digits as its factorization.

247813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1344, while the sum is 25.

The square root of 247813 is about 497.8081959952. The cubic root of 247813 is about 62.8118177281.

The spelling of 247813 in words is "two hundred forty-seven thousand, eight hundred thirteen".