2778655526820 has 480 divisors, whose sum is σ = 9090255525120. Its totient is φ = 709962485760.

The previous prime is 2778655526791. The next prime is 2778655526827. The reversal of 2778655526820 is 286255568772.

2778655526820 is a `hidden beast` number, since 2 + 7 + 7 + 86 + 5 + 5 + 526 + 8 + 20 = 666.

2778655526820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (2778655526827) by changing a digit.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 1275196491 + ... + 1275198669.

It is an arithmetic number, because the mean of its divisors is an integer number (18938032344).

Almost surely, 2^{2778655526820} is an apocalyptic number.

2778655526820 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 2778655526820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4545127762560).

2778655526820 is an abundant number, since it is smaller than the sum of its proper divisors (6311599998300).

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

2778655526820 is a wasteful number, since it uses less digits than its factorization.

2778655526820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2577 (or 2566 counting only the distinct ones).

The product of its (nonzero) digits is 112896000, while the sum is 63.

The spelling of 2778655526820 in words is "two trillion, seven hundred seventy-eight billion, six hundred fifty-five million, five hundred twenty-six thousand, eight hundred twenty".