261245 has 4 divisors (see below), whose sum is σ = 313500. Its totient is φ = 208992.

The previous prime is 261241. The next prime is 261251. The reversal of 261245 is 542162.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 32761 + 228484 = 181^2 + 478^2 .

It is a cyclic number.

It is not a de Polignac number, because 261245 - 2² = 261241 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261241) 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, 26120 + ... + 26129.

It is an arithmetic number, because the mean of its divisors is an integer number (78375).

2²⁶¹²⁴⁵ is an apocalyptic number.

It is an amenable number.

261245 is a deficient number, since it is larger than the sum of its proper divisors (52255).

261245 is an equidigital number, since it uses as much as digits as its factorization.

261245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52254.

The product of its digits is 480, while the sum is 20.

The square root of 261245 is about 511.1213163232. The cubic root of 261245 is about 63.9267554001.

The spelling of 261245 in words is "two hundred sixty-one thousand, two hundred forty-five".