261439487756782 has 16 divisors (see below), whose sum is σ = 405201407098752. Its totient is φ = 126380516175360.

The previous prime is 261439487756779. The next prime is 261439487756809. The reversal of 261439487756782 is 287657784934162.

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 7 ways as a sum of consecutive naturals, for example, 2040964963 + ... + 2041093054.

It is an arithmetic number, because the mean of its divisors is an integer number (25325087943672).

Almost surely, 2^{261439487756782} is an apocalyptic number.

261439487756782 is a deficient number, since it is larger than the sum of its proper divisors (143761919341970).

261439487756782 is a wasteful number, since it uses less digits than its factorization.

261439487756782 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4082059083.

The product of its digits is 6827950080, while the sum is 79.

The spelling of 261439487756782 in words is "two hundred sixty-one trillion, four hundred thirty-nine billion, four hundred eighty-seven million, seven hundred fifty-six thousand, seven hundred eighty-two".