261171156 has 48 divisors (see below), whose sum is σ = 637091840. Its totient is φ = 83172960.

The previous prime is 261171143. The next prime is 261171179. The reversal of 261171156 is 651171162.

261171156 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24945 + ... + 33831.

Almost surely, 2^261171156 is an apocalyptic number.

It is an amenable number.

261171156 is an abundant number, since it is smaller than the sum of its proper divisors (375920684).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261171156 is a wasteful number, since it uses less digits than its factorization.

261171156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9004 (or 9002 counting only the distinct ones).

The product of its digits is 2520, while the sum is 30.

The square root of 261171156 is about 16160.7906984776. The cubic root of 261171156 is about 639.2073161381.

The spelling of 261171156 in words is "two hundred sixty-one million, one hundred seventy-one thousand, one hundred fifty-six".