247939 has 2 divisors, whose sum is σ = 247940. Its totient is φ = 247938.

The previous prime is 247913. The next prime is 247943. The reversal of 247939 is 939742.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 247939 - 2⁷ = 247811 is a prime.

It is a super-2 number, since 2×247939² = 122947495442, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (247999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123969 + 123970.

It is an arithmetic number, because the mean of its divisors is an integer number (123970).

2²⁴⁷⁹³⁹ is an apocalyptic number.

247939 is a deficient number, since it is larger than the sum of its proper divisors (1).

247939 is an equidigital number, since it uses as much as digits as its factorization.

247939 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13608, while the sum is 34.

The square root of 247939 is about 497.9347346792. The cubic root of 247939 is about 62.8224614367.

The spelling of 247939 in words is "two hundred forty-seven thousand, nine hundred thirty-nine".