261840328 has 8 divisors (see below), whose sum is σ = 490950630. Its totient is φ = 130920160.

The previous prime is 261840259. The next prime is 261840343. The reversal of 261840328 is 823048162.

It can be written as a sum of positive squares in only one way, i.e., 207994084 + 53846244 = 14422^2 + 7338^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 261840293 and 261840302.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16365013 + ... + 16365028.

Almost surely, 2^261840328 is an apocalyptic number.

It is an amenable number.

261840328 is a deficient number, since it is larger than the sum of its proper divisors (229110302).

261840328 is a wasteful number, since it uses less digits than its factorization.

261840328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32730047 (or 32730043 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 34.

The square root of 261840328 is about 16181.4810199808. The cubic root of 261840328 is about 639.7527756062.

The spelling of 261840328 in words is "two hundred sixty-one million, eight hundred forty thousand, three hundred twenty-eight".