261761040 has 60 divisors (see below), whose sum is σ = 879083244. Its totient is φ = 69802752.

The previous prime is 261761033. The next prime is 261761041. The reversal of 261761040 is 40167162.

261761040 is a `hidden beast` number, since 2 + 6 + 1 + 7 + 610 + 40 = 666.

261761040 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 114575616 + 147185424 = 10704^2 + 12132^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a junction number, because it is equal to n+sod(n) for n = 261760995 and 261761013.

It is not an unprimeable number, because it can be changed into a prime (261761041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 181059 + ... + 182498.

Almost surely, 2^261761040 is an apocalyptic number.

261761040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261761040 is an abundant number, since it is smaller than the sum of its proper divisors (617322204).

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

261761040 is a wasteful number, since it uses less digits than its factorization.

261761040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363576 (or 363567 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 261761040 is about 16179.0308733249. The cubic root of 261761040 is about 639.6881944684.

The spelling of 261761040 in words is "two hundred sixty-one million, seven hundred sixty-one thousand, forty".