261323523633611 has 4 divisors (see below), whose sum is σ = 261447197806872. Its totient is φ = 261199849460352.

The previous prime is 261323523633581. The next prime is 261323523633647. The reversal of 261323523633611 is 116336325323162.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 261323523633611 - 2³⁸ = 261048645726667 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261323523633311) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61837083461 + ... + 61837087686.

It is an arithmetic number, because the mean of its divisors is an integer number (65361799451718).

Almost surely, 2^{261323523633611} is an apocalyptic number.

261323523633611 is a deficient number, since it is larger than the sum of its proper divisors (123674173261).

261323523633611 is a wasteful number, since it uses less digits than its factorization.

261323523633611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123674173260.

The product of its digits is 2099520, while the sum is 47.

Adding to 261323523633611 its reverse (116336325323162), we get a palindrome (377659848956773).

The spelling of 261323523633611 in words is "two hundred sixty-one trillion, three hundred twenty-three billion, five hundred twenty-three million, six hundred thirty-three thousand, six hundred eleven".