247905 has 24 divisors (see below), whose sum is σ = 491712. Its totient is φ = 113184.

The previous prime is 247901. The next prime is 247913. The reversal of 247905 is 509742.

It is not a de Polignac number, because 247905 - 2² = 247901 is a prime.

It is a super-2 number, since 2×247905² = 122913778050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (247901) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 79 + ... + 708.

It is an arithmetic number, because the mean of its divisors is an integer number (20488).

2²⁴⁷⁹⁰⁵ is an apocalyptic number.

It is an amenable number.

247905 is a deficient number, since it is larger than the sum of its proper divisors (243807).

247905 is a wasteful number, since it uses less digits than its factorization.

247905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 805 (or 802 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 247905 is about 497.9005924881. The cubic root of 247905 is about 62.8195896802.

The spelling of 247905 in words is "two hundred forty-seven thousand, nine hundred five".