261439 has 2 divisors, whose sum is σ = 261440. Its totient is φ = 261438.

The previous prime is 261433. The next prime is 261451. The reversal of 261439 is 934162.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261439 - 2³ = 261431 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130719 + 130720.

It is an arithmetic number, because the mean of its divisors is an integer number (130720).

2²⁶¹⁴³⁹ is an apocalyptic number.

261439 is a deficient number, since it is larger than the sum of its proper divisors (1).

261439 is an equidigital number, since it uses as much as digits as its factorization.

261439 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 25.

The square root of 261439 is about 511.3110599234. The cubic root of 261439 is about 63.9425754439.

The spelling of 261439 in words is "two hundred sixty-one thousand, four hundred thirty-nine".