261043873524 has 192 divisors, whose sum is σ = 819354009600. Its totient is φ = 70163006976.

The previous prime is 261043873511. The next prime is 261043873553. The reversal of 261043873524 is 425378340162.

261043873524 is a `hidden beast` number, since 2 + 6 + 1 + 0 + 43 + 87 + 3 + 524 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 261043873524.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 38848237 + ... + 38854955.

It is an arithmetic number, because the mean of its divisors is an integer number (4267468800).

Almost surely, 2^261043873524 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261043873524, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (409677004800).

261043873524 is an abundant number, since it is smaller than the sum of its proper divisors (558310136076).

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

261043873524 is a wasteful number, since it uses less digits than its factorization.

261043873524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9779 (or 9771 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 45.

The spelling of 261043873524 in words is "two hundred sixty-one billion, forty-three million, eight hundred seventy-three thousand, five hundred twenty-four".