247381 has 2 divisors, whose sum is σ = 247382. Its totient is φ = 247380.

The previous prime is 247369. The next prime is 247391. The reversal of 247381 is 183742.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 194481 + 52900 = 441^2 + 230^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-247381 is a prime.

It is a super-2 number, since 2×247381² = 122394718322, which contains 22 as substring.

247381 is a lucky number.

It is a nialpdrome in base 14.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (247301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123690 + 123691.

It is an arithmetic number, because the mean of its divisors is an integer number (123691).

2²⁴⁷³⁸¹ is an apocalyptic number.

It is an amenable number.

247381 is a deficient number, since it is larger than the sum of its proper divisors (1).

247381 is an equidigital number, since it uses as much as digits as its factorization.

247381 is an evil number, because the sum of its binary digits is even.

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

The square root of 247381 is about 497.3741046737. The cubic root of 247381 is about 62.7752975993.

The spelling of 247381 in words is "two hundred forty-seven thousand, three hundred eighty-one".