261084455808 has 64 divisors (see below), whose sum is σ = 756551560320. Its totient is φ = 79116500480.

The previous prime is 261084455773. The next prime is 261084455813. The reversal of 261084455808 is 808554480162.

It is a tau number, because it is divible by the number of its divisors (64).

It is a hoax number, since the sum of its digits (51) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

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 in 7 ways as a sum of consecutive naturals, for example, 30900660 + ... + 30909107.

It is an arithmetic number, because the mean of its divisors is an integer number (11821118130).

Almost surely, 2^261084455808 is an apocalyptic number.

It is an amenable number.

261084455808 is an abundant number, since it is smaller than the sum of its proper divisors (495467104512).

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

261084455808 is a wasteful number, since it uses less digits than its factorization.

261084455808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61809795 (or 61809783 counting only the distinct ones).

The product of its (nonzero) digits is 2457600, while the sum is 51.

The spelling of 261084455808 in words is "two hundred sixty-one billion, eighty-four million, four hundred fifty-five thousand, eight hundred eight".