261574417776555 has 96 divisors (see below), whose sum is σ = 504349669404672. Its totient is φ = 124540283808000.

The previous prime is 261574417776541. The next prime is 261574417776557. The reversal of 261574417776555 is 555677714475162.

261574417776555 is a `hidden beast` number, since 2 + 6 + 1 + 5 + 7 + 441 + 7 + 77 + 65 + 55 = 666.

It is not a de Polignac number, because 261574417776555 - 2¹⁸ = 261574417514411 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261574417776557) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 23308380 + ... + 32656230.

It is an arithmetic number, because the mean of its divisors is an integer number (5253642389632).

Almost surely, 2^{261574417776555} is an apocalyptic number.

261574417776555 is a deficient number, since it is larger than the sum of its proper divisors (242775251628117).

261574417776555 is a wasteful number, since it uses less digits than its factorization.

261574417776555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9349449 (or 9349446 counting only the distinct ones).

The product of its digits is 1728720000, while the sum is 72.

The spelling of 261574417776555 in words is "two hundred sixty-one trillion, five hundred seventy-four billion, four hundred seventeen million, seven hundred seventy-six thousand, five hundred fifty-five".