261867 has 8 divisors (see below), whose sum is σ = 357840. Its totient is φ = 170240.

The previous prime is 261847. The next prime is 261881. The reversal of 261867 is 768162.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261867 - 2⁷ = 261739 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 942 + ... + 1187.

It is an arithmetic number, because the mean of its divisors is an integer number (44730).

261867 is a Friedman number, since it can be written as 8^6-271-6, using all its digits and the basic arithmetic operations.

2²⁶¹⁸⁶⁷ is an apocalyptic number.

261867 is a deficient number, since it is larger than the sum of its proper divisors (95973).

261867 is a wasteful number, since it uses less digits than its factorization.

261867 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2173.

The product of its digits is 4032, while the sum is 30.

The square root of 261867 is about 511.7294206903. The cubic root of 261867 is about 63.9774497377.

It can be divided in two parts, 261 and 867, that added together give a triangular number (1128 = T₄₇).

The spelling of 261867 in words is "two hundred sixty-one thousand, eight hundred sixty-seven".