261025 has 12 divisors (see below), whose sum is σ = 331452. Its totient is φ = 203840.

The previous prime is 261017. The next prime is 261031. The reversal of 261025 is 520162.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 21904 + 239121 = 148^2 + 489^2 .

It is not a de Polignac number, because 261025 - 2³ = 261017 is a prime.

It is a Duffinian number.

261025 is a lucky number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1227 + ... + 1423.

It is an arithmetic number, because the mean of its divisors is an integer number (27621).

2²⁶¹⁰²⁵ is an apocalyptic number.

261025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

261025 is a deficient number, since it is larger than the sum of its proper divisors (70427).

261025 is a wasteful number, since it uses less digits than its factorization.

261025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260 (or 255 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 261025 is about 510.9060579011. The cubic root of 261025 is about 63.9088056647.

Adding to 261025 its reverse (520162), we get a palindrome (781187).

The spelling of 261025 in words is "two hundred sixty-one thousand, twenty-five".