261265266920659 has 8 divisors (see below), whose sum is σ = 278425150318080. Its totient is φ = 244588760520456.

The previous prime is 261265266920657. The next prime is 261265266920687. The reversal of 261265266920659 is 956029662562162.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 261265266920659 - 2¹ = 261265266920657 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 261265266920594 and 261265266920603.

It is not an unprimeable number, because it can be changed into a prime (261265266920657) by changing a digit.

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, 120844248189 + ... + 120844250350.

It is an arithmetic number, because the mean of its divisors is an integer number (34803143789760).

Almost surely, 2^{261265266920659} is an apocalyptic number.

261265266920659 is a deficient number, since it is larger than the sum of its proper divisors (17159883397421).

261265266920659 is a wasteful number, since it uses less digits than its factorization.

261265266920659 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241688498609.

The product of its (nonzero) digits is 251942400, while the sum is 67.

The spelling of 261265266920659 in words is "two hundred sixty-one trillion, two hundred sixty-five billion, two hundred sixty-six million, nine hundred twenty thousand, six hundred fifty-nine".