261443161 has 8 divisors (see below), whose sum is σ = 299113344. Its totient is φ = 223853280.

The previous prime is 261443141. The next prime is 261443167. The reversal of 261443161 is 161344162.

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

It is not a de Polignac number, because 261443161 - 2⁵ = 261443129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261443167) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12925 + ... + 26266.

It is an arithmetic number, because the mean of its divisors is an integer number (37389168).

Almost surely, 2^261443161 is an apocalyptic number.

It is an amenable number.

261443161 is a deficient number, since it is larger than the sum of its proper divisors (37670183).

261443161 is an equidigital number, since it uses as much as digits as its factorization.

261443161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40151.

The product of its digits is 3456, while the sum is 28.

The square root of 261443161 is about 16169.2040929664. The cubic root of 261443161 is about 639.4291467358.

The spelling of 261443161 in words is "two hundred sixty-one million, four hundred forty-three thousand, one hundred sixty-one".