261254640135225 has 24 divisors (see below), whose sum is σ = 471208369118112. Its totient is φ = 126668916428800.

The previous prime is 261254640135221. The next prime is 261254640135239. The reversal of 261254640135225 is 522531046452162.

It is not a de Polignac number, because 261254640135225 - 2² = 261254640135221 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261254640135221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 158336144712 + ... + 158336146361.

It is an arithmetic number, because the mean of its divisors is an integer number (19633682046588).

Almost surely, 2^{261254640135225} is an apocalyptic number.

261254640135225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

261254640135225 is a deficient number, since it is larger than the sum of its proper divisors (209953728982887).

261254640135225 is a wasteful number, since it uses less digits than its factorization.

261254640135225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316672291097 (or 316672291092 counting only the distinct ones).

The product of its (nonzero) digits is 3456000, while the sum is 48.

Adding to 261254640135225 its reverse (522531046452162), we get a palindrome (783785686587387).

The spelling of 261254640135225 in words is "two hundred sixty-one trillion, two hundred fifty-four billion, six hundred forty million, one hundred thirty-five thousand, two hundred twenty-five".