261941760 has 120 divisors (see below), whose sum is σ = 907257780. Its totient is φ = 69844992.

The previous prime is 261941753. The next prime is 261941761. The reversal of 261941760 is 67149162.

It can be written as a sum of positive squares in 2 ways, for example, as 261662976 + 278784 = 16176^2 + 528^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×261941760² = 137226971263795200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (261941761) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 17356 + ... + 28724.

Almost surely, 2^261941760 is an apocalyptic number.

261941760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261941760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (453628890).

261941760 is an abundant number, since it is smaller than the sum of its proper divisors (645316020).

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

261941760 is a wasteful number, since it uses less digits than its factorization.

261941760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11398 (or 11379 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 261941760 is about 16184.6149166423. The cubic root of 261941760 is about 639.8353743240.

The spelling of 261941760 in words is "two hundred sixty-one million, nine hundred forty-one thousand, seven hundred sixty".