261135556 has 12 divisors (see below), whose sum is σ = 498531600. Its totient is φ = 118697960.

The previous prime is 261135541. The next prime is 261135557. The reversal of 261135556 is 655531162.

It is not an unprimeable number, because it can be changed into a prime (261135557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2967406 + ... + 2967493.

It is an arithmetic number, because the mean of its divisors is an integer number (41544300).

Almost surely, 2^261135556 is an apocalyptic number.

It is an amenable number.

261135556 is a deficient number, since it is larger than the sum of its proper divisors (237396044).

261135556 is a wasteful number, since it uses less digits than its factorization.

261135556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5934914 (or 5934912 counting only the distinct ones).

The product of its digits is 27000, while the sum is 34.

The square root of 261135556 is about 16159.6892296851. The cubic root of 261135556 is about 639.1782715646.

The spelling of 261135556 in words is "two hundred sixty-one million, one hundred thirty-five thousand, five hundred fifty-six".