261793065600 has 2304 divisors, whose sum is σ = 1174381977600. Its totient is φ = 54743040000.

The previous prime is 261793065587. The next prime is 261793065629. The reversal of 261793065600 is 6560397162.

261793065600 is a `hidden beast` number, since 2 + 6 + 1 + 7 + 9 + 30 + 6 + 5 + 600 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 4291689570 + ... + 4291689630.

It is an arithmetic number, because the mean of its divisors is an integer number (509714400).

Almost surely, 2^261793065600 is an apocalyptic number.

261793065600 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 261793065600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (587190988800).

261793065600 is an abundant number, since it is smaller than the sum of its proper divisors (912588912000).

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

261793065600 is a wasteful number, since it uses less digits than its factorization.

261793065600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 408240, while the sum is 45.

The spelling of 261793065600 in words is "two hundred sixty-one billion, seven hundred ninety-three million, sixty-five thousand, six hundred".