261140161 has 16 divisors (see below), whose sum is σ = 284739840. Its totient is φ = 238669200.

The previous prime is 261140153. The next prime is 261140167. The reversal of 261140161 is 161041162.

261140161 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 261140161 - 2³ = 261140153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261140167) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65886 + ... + 69736.

It is an arithmetic number, because the mean of its divisors is an integer number (17796240).

Almost surely, 2^261140161 is an apocalyptic number.

It is an amenable number.

261140161 is a deficient number, since it is larger than the sum of its proper divisors (23599679).

261140161 is a wasteful number, since it uses less digits than its factorization.

261140161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3996.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 261140161 is about 16159.8317132327. The cubic root of 261140161 is about 639.1820287431.

The spelling of 261140161 in words is "two hundred sixty-one million, one hundred forty thousand, one hundred sixty-one".