261243 has 6 divisors (see below), whose sum is σ = 377364. Its totient is φ = 174156.

The previous prime is 261241. The next prime is 261251. The reversal of 261243 is 342162.

It is a happy number.

It is not a de Polignac number, because 261243 - 2¹ = 261241 is a prime.

261243 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (261241) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 14505 + ... + 14522.

It is an arithmetic number, because the mean of its divisors is an integer number (62894).

2²⁶¹²⁴³ is an apocalyptic number.

261243 is a deficient number, since it is larger than the sum of its proper divisors (116121).

261243 is a wasteful number, since it uses less digits than its factorization.

261243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29033 (or 29030 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 261243 is about 511.1193598368. The cubic root of 261243 is about 63.9265922661.

The spelling of 261243 in words is "two hundred sixty-one thousand, two hundred forty-three".