261223953205 has 8 divisors (see below), whose sum is σ = 315544696704. Its totient is φ = 207595194000.

The previous prime is 261223953203. The next prime is 261223953233. The reversal of 261223953205 is 502359322162.

261223953205 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 261223953205 - 2¹ = 261223953203 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261223953203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 172995241 + ... + 172996750.

It is an arithmetic number, because the mean of its divisors is an integer number (39443087088).

Almost surely, 2^261223953205 is an apocalyptic number.

It is an amenable number.

261223953205 is a deficient number, since it is larger than the sum of its proper divisors (54320743499).

261223953205 is a wasteful number, since it uses less digits than its factorization.

261223953205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345992147.

The product of its (nonzero) digits is 194400, while the sum is 40.

The spelling of 261223953205 in words is "two hundred sixty-one billion, two hundred twenty-three million, nine hundred fifty-three thousand, two hundred five".