261251035 has 4 divisors (see below), whose sum is σ = 313501248. Its totient is φ = 209000824.

The previous prime is 261251033. The next prime is 261251041. The reversal of 261251035 is 530152162.

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

It is a cyclic number.

It is not a de Polignac number, because 261251035 - 2¹ = 261251033 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261251033) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26125099 + ... + 26125108.

It is an arithmetic number, because the mean of its divisors is an integer number (78375312).

Almost surely, 2^261251035 is an apocalyptic number.

261251035 is a deficient number, since it is larger than the sum of its proper divisors (52250213).

261251035 is an equidigital number, since it uses as much as digits as its factorization.

261251035 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52250212.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 261251035 is about 16163.2618923285. The cubic root of 261251035 is about 639.2724765198.

The spelling of 261251035 in words is "two hundred sixty-one million, two hundred fifty-one thousand, thirty-five".