261528948576 has 576 divisors, whose sum is σ = 928241233920. Its totient is φ = 68160061440.

The previous prime is 261528948547. The next prime is 261528948643. The reversal of 261528948576 is 675849825162.

261528948576 is a `hidden beast` number, since 2 + 6 + 1 + 5 + 2 + 89 + 485 + 76 = 666.

261528948576 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

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 95 ways as a sum of consecutive naturals, for example, 305167540 + ... + 305168396.

It is an arithmetic number, because the mean of its divisors is an integer number (1611529920).

Almost surely, 2^261528948576 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 261528948576, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (464120616960).

261528948576 is an abundant number, since it is smaller than the sum of its proper divisors (666712285344).

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

261528948576 is a wasteful number, since it uses less digits than its factorization.

261528948576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1187 (or 1176 counting only the distinct ones).

The product of its digits is 58060800, while the sum is 63.

The spelling of 261528948576 in words is "two hundred sixty-one billion, five hundred twenty-eight million, nine hundred forty-eight thousand, five hundred seventy-six".