261571275 has 72 divisors (see below), whose sum is σ = 555353344. Its totient is φ = 119556000.

The previous prime is 261571243. The next prime is 261571301. The reversal of 261571275 is 572175162.

261571275 is a `hidden beast` number, since 2 + 61 + 571 + 27 + 5 = 666.

It is not a de Polignac number, because 261571275 - 2⁵ = 261571243 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 39450 + ... + 45600.

Almost surely, 2^261571275 is an apocalyptic number.

261571275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

261571275 is an abundant number, since it is smaller than the sum of its proper divisors (293782069).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261571275 is an equidigital number, since it uses as much as digits as its factorization.

261571275 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6183 (or 6166 counting only the distinct ones).

The product of its digits is 29400, while the sum is 36.

The square root of 261571275 is about 16173.1652746146. The cubic root of 261571275 is about 639.5335753595.

It can be divided in two parts, 261 and 571275, that added together give a square (571536 = 756²).

The spelling of 261571275 in words is "two hundred sixty-one million, five hundred seventy-one thousand, two hundred seventy-five".