261591847228800 has 2304 divisors, whose sum is σ = 1112792976691200. Its totient is φ = 59870638080000.

The previous prime is 261591847228757. The next prime is 261591847228819. The reversal of 261591847228800 is 8822748195162.

261591847228800 is a `hidden beast` number, since 2 + 6 + 1 + 59 + 18 + 472 + 28 + 80 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 13287532557 + ... + 13287552243.

It is an arithmetic number, because the mean of its divisors is an integer number (482983062800).

Almost surely, 2^{261591847228800} is an apocalyptic number.

261591847228800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261591847228800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (556396488345600).

261591847228800 is an abundant number, since it is smaller than the sum of its proper divisors (851201129462400).

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

261591847228800 is a wasteful number, since it uses less digits than its factorization.

261591847228800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19814 (or 19780 counting only the distinct ones).

The product of its (nonzero) digits is 30965760, while the sum is 63.

The spelling of 261591847228800 in words is "two hundred sixty-one trillion, five hundred ninety-one billion, eight hundred forty-seven million, two hundred twenty-eight thousand, eight hundred".