261122810247 has 12 divisors (see below), whose sum is σ = 406191038344. Its totient is φ = 160690960080.

The previous prime is 261122810233. The next prime is 261122810293. The reversal of 261122810247 is 742018221162.

261122810247 is a `hidden beast` number, since 2 + 611 + 2 + 2 + 8 + 10 + 24 + 7 = 666.

It is not a de Polignac number, because 261122810247 - 2¹⁰ = 261122809223 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261122810747) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1115909329 + ... + 1115909562.

Almost surely, 2^261122810247 is an apocalyptic number.

261122810247 is a deficient number, since it is larger than the sum of its proper divisors (145068228097).

261122810247 is a wasteful number, since it uses less digits than its factorization.

261122810247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2231818910 (or 2231818907 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The spelling of 261122810247 in words is "two hundred sixty-one billion, one hundred twenty-two million, eight hundred ten thousand, two hundred forty-seven".