261665710201156 has 24 divisors (see below), whose sum is σ = 484868130679296. Its totient is φ = 123132497047680.

The previous prime is 261665710201127. The next prime is 261665710201157. The reversal of 261665710201156 is 651102017566162.

It is not an unprimeable number, because it can be changed into a prime (261665710201157) 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, 65350156 + ... + 69238531.

It is an arithmetic number, because the mean of its divisors is an integer number (20202838778304).

Almost surely, 2^{261665710201156} is an apocalyptic number.

It is an amenable number.

261665710201156 is a deficient number, since it is larger than the sum of its proper divisors (223202420478140).

261665710201156 is a wasteful number, since it uses less digits than its factorization.

261665710201156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134617299 (or 134617297 counting only the distinct ones).

The product of its (nonzero) digits is 907200, while the sum is 49.

The spelling of 261665710201156 in words is "two hundred sixty-one trillion, six hundred sixty-five billion, seven hundred ten million, two hundred one thousand, one hundred fifty-six".