261618744000 has 896 divisors, whose sum is σ = 951736780800. Its totient is φ = 63109939200.

The previous prime is 261618743999. The next prime is 261618744007. The reversal of 261618744000 is 447816162.

261618744000 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 261618744000.

It is not an unprimeable number, because it can be changed into a prime (261618744007) by changing a digit.

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 127 ways as a sum of consecutive naturals, for example, 944471862 + ... + 944472138.

Almost surely, 2^261618744000 is an apocalyptic number.

261618744000 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 261618744000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (475868390400).

261618744000 is an abundant number, since it is smaller than the sum of its proper divisors (690118036800).

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

261618744000 is a wasteful number, since it uses less digits than its factorization.

261618744000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418 (or 398 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 39.

The spelling of 261618744000 in words is "two hundred sixty-one billion, six hundred eighteen million, seven hundred forty-four thousand".