261540563200 has 216 divisors, whose sum is σ = 778773974720. Its totient is φ = 84951244800.

The previous prime is 261540563173. The next prime is 261540563261. The reversal of 261540563200 is 2365045162.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 697570 + ... + 1004830.

Almost surely, 2^261540563200 is an apocalyptic number.

261540563200 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 261540563200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (389386987360).

261540563200 is an abundant number, since it is smaller than the sum of its proper divisors (517233411520).

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

261540563200 is a wasteful number, since it uses less digits than its factorization.

261540563200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307313 (or 307294 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 34.

The spelling of 261540563200 in words is "two hundred sixty-one billion, five hundred forty million, five hundred sixty-three thousand, two hundred".