261436 has 12 divisors (see below), whose sum is σ = 522928. Its totient is φ = 112032.

The previous prime is 261433. The next prime is 261439. The reversal of 261436 is 634162.

It is an interprime number because it is at equal distance from previous prime (261433) and next prime (261439).

261436 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4641 + ... + 4696.

2²⁶¹⁴³⁶ is an apocalyptic number.

It is an amenable number.

261436 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261436 is a wasteful number, since it uses less digits than its factorization.

261436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9348 (or 9346 counting only the distinct ones).

The product of its digits is 864, while the sum is 22.

The square root of 261436 is about 511.3081262800. The cubic root of 261436 is about 63.9423308636.

Adding to 261436 its reverse (634162), we get a palindrome (895598).

The spelling of 261436 in words is "two hundred sixty-one thousand, four hundred thirty-six".