261487 has 4 divisors (see below), whose sum is σ = 272880. Its totient is φ = 250096.

The previous prime is 261467. The next prime is 261509. The reversal of 261487 is 784162.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261487 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 (261407) 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, 5662 + ... + 5707.

It is an arithmetic number, because the mean of its divisors is an integer number (68220).

2²⁶¹⁴⁸⁷ is an apocalyptic number.

261487 is a deficient number, since it is larger than the sum of its proper divisors (11393).

261487 is a wasteful number, since it uses less digits than its factorization.

261487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11392.

The product of its digits is 2688, while the sum is 28.

The square root of 261487 is about 511.3579959285. The cubic root of 261487 is about 63.9464884737.

It can be divided in two parts, 2614 and 87, that added together give a triangular number (2701 = T₇₃).

The spelling of 261487 in words is "two hundred sixty-one thousand, four hundred eighty-seven".