261603220535 has 8 divisors (see below), whose sum is σ = 314120445216. Its totient is φ = 209151522720.

The previous prime is 261603220517. The next prime is 261603220547. The reversal of 261603220535 is 535022306162.

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

It is not a de Polignac number, because 261603220535 - 2³⁶ = 192883743799 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 261603220495 and 261603220504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16372931 + ... + 16388900.

It is an arithmetic number, because the mean of its divisors is an integer number (39265055652).

Almost surely, 2^261603220535 is an apocalyptic number.

261603220535 is a deficient number, since it is larger than the sum of its proper divisors (52517224681).

261603220535 is a wasteful number, since it uses less digits than its factorization.

261603220535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32763433.

The product of its (nonzero) digits is 64800, while the sum is 35.

Adding to 261603220535 its reverse (535022306162), we get a palindrome (796625526697).

The spelling of 261603220535 in words is "two hundred sixty-one billion, six hundred three million, two hundred twenty thousand, five hundred thirty-five".