261172160 has 28 divisors (see below), whose sum is σ = 621916968. Its totient is φ = 104468736.

The previous prime is 261172133. The next prime is 261172189. The reversal of 261172160 is 61271162.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 407762 + ... + 408401.

Almost surely, 2^261172160 is an apocalyptic number.

261172160 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261172160 is an abundant number, since it is smaller than the sum of its proper divisors (360744808).

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

261172160 is an equidigital number, since it uses as much as digits as its factorization.

261172160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 816180 (or 816170 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 261172160 is about 16160.8217612843. The cubic root of 261172160 is about 639.2081352221.

The spelling of 261172160 in words is "two hundred sixty-one million, one hundred seventy-two thousand, one hundred sixty".