261563351242364 has 12 divisors (see below), whose sum is σ = 457736011509504. Its totient is φ = 130781633668224.

The previous prime is 261563351242351. The next prime is 261563351242379. The reversal of 261563351242364 is 463242153365162.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6652229 + ... + 23819715.

It is an arithmetic number, because the mean of its divisors is an integer number (38144667625792).

Almost surely, 2^{261563351242364} is an apocalyptic number.

It is an amenable number.

261563351242364 is a deficient number, since it is larger than the sum of its proper divisors (196172660267140).

261563351242364 is a wasteful number, since it uses less digits than its factorization.

261563351242364 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20976484 (or 20976482 counting only the distinct ones).

The product of its digits is 18662400, while the sum is 53.

The spelling of 261563351242364 in words is "two hundred sixty-one trillion, five hundred sixty-three billion, three hundred fifty-one million, two hundred forty-two thousand, three hundred sixty-four".