261766655 has 16 divisors (see below), whose sum is σ = 320785920. Its totient is φ = 205008672.

The previous prime is 261766621. The next prime is 261766679. The reversal of 261766655 is 556667162.

It is a cyclic number.

It is not a de Polignac number, because 261766655 - 2¹² = 261762559 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53606 + ... + 58284.

It is an arithmetic number, because the mean of its divisors is an integer number (20049120).

Almost surely, 2^261766655 is an apocalyptic number.

261766655 is a deficient number, since it is larger than the sum of its proper divisors (59019265).

261766655 is a wasteful number, since it uses less digits than its factorization.

261766655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4918.

The product of its digits is 453600, while the sum is 44.

The square root of 261766655 is about 16179.2043994753. The cubic root of 261766655 is about 639.6927683901.

The spelling of 261766655 in words is "two hundred sixty-one million, seven hundred sixty-six thousand, six hundred fifty-five".