261015853668 has 12 divisors (see below), whose sum is σ = 609036991920. Its totient is φ = 87005284552.

The previous prime is 261015853667. The next prime is 261015853669. The reversal of 261015853668 is 866358510162.

It is a happy number.

261015853668 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (261015853667) and next prime (261015853669).

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 261015853668.

It is not an unprimeable number, because it can be changed into a prime (261015853667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10875660558 + ... + 10875660581.

It is an arithmetic number, because the mean of its divisors is an integer number (50753082660).

Almost surely, 2^261015853668 is an apocalyptic number.

It is an amenable number.

261015853668 is an abundant number, since it is smaller than the sum of its proper divisors (348021138252).

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

261015853668 is a wasteful number, since it uses less digits than its factorization.

261015853668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21751321146 (or 21751321144 counting only the distinct ones).

The product of its (nonzero) digits is 2073600, while the sum is 51.

The spelling of 261015853668 in words is "two hundred sixty-one billion, fifteen million, eight hundred fifty-three thousand, six hundred sixty-eight".