261243861327 has 12 divisors (see below), whose sum is σ = 384472098504. Its totient is φ = 170876487600.

The previous prime is 261243861317. The next prime is 261243861343. The reversal of 261243861327 is 723168342162.

261243861327 is a `hidden beast` number, since 2 + 6 + 1 + 2 + 4 + 3 + 8 + 613 + 27 = 666.

It is not a de Polignac number, because 261243861327 - 2¹⁰ = 261243860303 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261243861317) 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 11 ways as a sum of consecutive naturals, for example, 273840049 + ... + 273841002.

It is an arithmetic number, because the mean of its divisors is an integer number (32039341542).

Almost surely, 2^261243861327 is an apocalyptic number.

261243861327 is a deficient number, since it is larger than the sum of its proper divisors (123228237177).

261243861327 is a wasteful number, since it uses less digits than its factorization.

261243861327 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 547681110 (or 547681107 counting only the distinct ones).

The product of its digits is 580608, while the sum is 45.

The spelling of 261243861327 in words is "two hundred sixty-one billion, two hundred forty-three million, eight hundred sixty-one thousand, three hundred twenty-seven".