247647 has 4 divisors (see below), whose sum is σ = 330200. Its totient is φ = 165096.

The previous prime is 247633. The next prime is 247649. The reversal of 247647 is 746742.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 247647 - 2⁷ = 247519 is a prime.

It is a super-2 number, since 2×247647² = 122658073218, which contains 22 as substring.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (247649) 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, 41272 + ... + 41277.

It is an arithmetic number, because the mean of its divisors is an integer number (82550).

2²⁴⁷⁶⁴⁷ is an apocalyptic number.

247647 is a deficient number, since it is larger than the sum of its proper divisors (82553).

247647 is an equidigital number, since it uses as much as digits as its factorization.

247647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82552.

The product of its digits is 9408, while the sum is 30.

The square root of 247647 is about 497.6414371814. The cubic root of 247647 is about 62.7977895553.

The spelling of 247647 in words is "two hundred forty-seven thousand, six hundred forty-seven".