861239 has 2 divisors, whose sum is σ = 861240. Its totient is φ = 861238.

The previous prime is 861221. The next prime is 861293. The reversal of 861239 is 932168.

861239 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with next prime (861293) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 861239 - 2¹⁶ = 795703 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (861299) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430619 + 430620.

It is an arithmetic number, because the mean of its divisors is an integer number (430620).

2⁸⁶¹²³⁹ is an apocalyptic number.

861239 is a deficient number, since it is larger than the sum of its proper divisors (1).

861239 is an equidigital number, since it uses as much as digits as its factorization.

861239 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2592, while the sum is 29.

The square root of 861239 is about 928.0296331476. The cubic root of 861239 is about 95.1425008221.

The spelling of 861239 in words is "eight hundred sixty-one thousand, two hundred thirty-nine".