261075 has 18 divisors (see below), whose sum is σ = 439084. Its totient is φ = 136880.

The previous prime is 261071. The next prime is 261077. The reversal of 261075 is 570162.

It is not a de Polignac number, because 261075 - 2² = 261071 is a prime.

It is a Duffinian number.

261075 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (261071) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 4396 + ... + 4454.

261075 is a Friedman number, since it can be written as 75*(60-1)^2, using all its digits and the basic arithmetic operations.

2²⁶¹⁰⁷⁵ is an apocalyptic number.

261075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

261075 is a deficient number, since it is larger than the sum of its proper divisors (178009).

261075 is an equidigital number, since it uses as much as digits as its factorization.

261075 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131 (or 67 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 261075 is about 510.9549882328. The cubic root of 261075 is about 63.9128860354.

The spelling of 261075 in words is "two hundred sixty-one thousand, seventy-five".