247805 has 8 divisors (see below), whose sum is σ = 307800. Its totient is φ = 191296.

The previous prime is 247799. The next prime is 247811. The reversal of 247805 is 508742.

It is an interprime number because it is at equal distance from previous prime (247799) and next prime (247811).

It can be written as a sum of positive squares in 4 ways, for example, as 6724 + 241081 = 82^2 + 491^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 247805 - 2¹⁰ = 246781 is a prime.

It is a super-2 number, since 2×247805² = 122814636050, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 710 + ... + 999.

It is an arithmetic number, because the mean of its divisors is an integer number (38475).

2²⁴⁷⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

247805 is a deficient number, since it is larger than the sum of its proper divisors (59995).

247805 is a wasteful number, since it uses less digits than its factorization.

247805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1743.

The product of its (nonzero) digits is 2240, while the sum is 26.

The square root of 247805 is about 497.8001607071. The cubic root of 247805 is about 62.8111418153.

The spelling of 247805 in words is "two hundred forty-seven thousand, eight hundred five".