261319 has 4 divisors (see below), whose sum is σ = 270360. Its totient is φ = 252280.

The previous prime is 261301. The next prime is 261323. The reversal of 261319 is 913162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 913162 = 2 ⋅456581.

It is a cyclic number.

It is not a de Polignac number, because 261319 - 2⁹ = 260807 is a prime.

It is a super-2 number, since 2×261319² = 136575239522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a self number, because there is not a number n which added to its sum of digits gives 261319.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261329) 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, 4477 + ... + 4534.

It is an arithmetic number, because the mean of its divisors is an integer number (67590).

2²⁶¹³¹⁹ is an apocalyptic number.

261319 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

261319 is a deficient number, since it is larger than the sum of its proper divisors (9041).

261319 is an equidigital number, since it uses as much as digits as its factorization.

261319 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9040.

The product of its digits is 324, while the sum is 22.

The square root of 261319 is about 511.1937010567. The cubic root of 261319 is about 63.9327907735.

The spelling of 261319 in words is "two hundred sixty-one thousand, three hundred nineteen".