261648078 has 8 divisors (see below), whose sum is σ = 523296168. Its totient is φ = 87216024.

The previous prime is 261648073. The next prime is 261648083. The reversal of 261648078 is 870846162.

It is an interprime number because it is at equal distance from previous prime (261648073) and next prime (261648083).

It is a sphenic number, since it is the product of 3 distinct primes.

261648078 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261648073) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 21804001 + ... + 21804012.

It is an arithmetic number, because the mean of its divisors is an integer number (65412021).

Almost surely, 2^261648078 is an apocalyptic number.

261648078 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

261648078 is a wasteful number, since it uses less digits than its factorization.

261648078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43608018.

The product of its (nonzero) digits is 129024, while the sum is 42.

The square root of 261648078 is about 16175.5394964125. The cubic root of 261648078 is about 639.5961628774.

The spelling of 261648078 in words is "two hundred sixty-one million, six hundred forty-eight thousand, seventy-eight".