2661868800 has 324 divisors, whose sum is σ = 9781817500. Its totient is φ = 690094080.

The previous prime is 2661868771. The next prime is 2661868801. The reversal of 2661868800 is 88681662.

2661868800 is a `hidden beast` number, since 26 + 618 + 6 + 8 + 8 + 0 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 4260096 + 2657608704 = 2064^2 + 51552^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2661868801) by changing a digit.

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 35 ways as a sum of consecutive naturals, for example, 2130576 + ... + 2131824.

Almost surely, 2^2661868800 is an apocalyptic number.

2661868800 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 2661868800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4890908750).

2661868800 is an abundant number, since it is smaller than the sum of its proper divisors (7119948700).

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

2661868800 is a wasteful number, since it uses less digits than its factorization.

2661868800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1318 (or 1296 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 45.

The square root of 2661868800 is about 51593.3018908463. The cubic root of 2661868800 is about 1385.8903856891.

The spelling of 2661868800 in words is "two billion, six hundred sixty-one million, eight hundred sixty-eight thousand, eight hundred".