261257360 has 160 divisors (see below), whose sum is σ = 791949312. Its totient is φ = 77783040.

The previous prime is 261257329. The next prime is 261257387. The reversal of 261257360 is 63752162.

261257360 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 31 ways as a sum of consecutive naturals, for example, 122705 + ... + 124815.

Almost surely, 2^261257360 is an apocalyptic number.

261257360 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 261257360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (395974656).

261257360 is an abundant number, since it is smaller than the sum of its proper divisors (530691952).

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

261257360 is a wasteful number, since it uses less digits than its factorization.

261257360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2161 (or 2155 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 261257360 is about 16163.4575509079. The cubic root of 261257360 is about 639.2776354987.

The spelling of 261257360 in words is "two hundred sixty-one million, two hundred fifty-seven thousand, three hundred sixty".