261743 has 4 divisors (see below), whose sum is σ = 267360. Its totient is φ = 256128.

The previous prime is 261739. The next prime is 261757. The reversal of 261743 is 347162.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 261743 - 2² = 261739 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261713) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2738 + ... + 2831.

It is an arithmetic number, because the mean of its divisors is an integer number (66840).

2²⁶¹⁷⁴³ is an apocalyptic number.

261743 is a deficient number, since it is larger than the sum of its proper divisors (5617).

261743 is an equidigital number, since it uses as much as digits as its factorization.

261743 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5616.

The product of its digits is 1008, while the sum is 23.

The square root of 261743 is about 511.6082485652. The cubic root of 261743 is about 63.9673498826.

The spelling of 261743 in words is "two hundred sixty-one thousand, seven hundred forty-three".