261184996800 has 2016 divisors, whose sum is σ = 1228999116800. Its totient is φ = 52533411840.

The previous prime is 261184996781. The next prime is 261184996823. The reversal of 261184996800 is 8699481162.

261184996800 is a `hidden beast` number, since 2 + 61 + 18 + 499 + 6 + 80 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2016).

It is a Harshad number since it is a multiple of its sum of digits (54).

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, 3306139161 + ... + 3306139239.

Almost surely, 2^261184996800 is an apocalyptic number.

261184996800 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 261184996800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (614499558400).

261184996800 is an abundant number, since it is smaller than the sum of its proper divisors (967814120000).

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

261184996800 is a wasteful number, since it uses less digits than its factorization.

261184996800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188 (or 138 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 54.

The spelling of 261184996800 in words is "two hundred sixty-one billion, one hundred eighty-four million, nine hundred ninety-six thousand, eight hundred".