261384560 has 40 divisors (see below), whose sum is σ = 627328896. Its totient is φ = 101180160.

The previous prime is 261384547. The next prime is 261384587. The reversal of 261384560 is 65483162.

261384560 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 261384560.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50219 + ... + 55178.

Almost surely, 2^261384560 is an apocalyptic number.

261384560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261384560 is an abundant number, since it is smaller than the sum of its proper divisors (365944336).

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

261384560 is a wasteful number, since it uses less digits than its factorization.

261384560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105441 (or 105435 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 35.

The square root of 261384560 is about 16167.3918737686. The cubic root of 261384560 is about 639.3813683618.

The spelling of 261384560 in words is "two hundred sixty-one million, three hundred eighty-four thousand, five hundred sixty".