2778891556608 has 180 divisors, whose sum is σ = 8287793109288. Its totient is φ = 926113720320.

The previous prime is 2778891556603. The next prime is 2778891556613. The reversal of 2778891556608 is 8066551988772.

2778891556608 is a `hidden beast` number, since 2 + 7 + 7 + 8 + 8 + 9 + 1 + 5 + 5 + 6 + 608 = 666.

It is an interprime number because it is at equal distance from previous prime (2778891556603) and next prime (2778891556613).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2778891556603) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 140600935 + ... + 140620697.

Almost surely, 2^{2778891556608} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2778891556608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4143896554644).

2778891556608 is an abundant number, since it is smaller than the sum of its proper divisors (5508901552680).

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

2778891556608 is an equidigital number, since it uses as much as digits as its factorization.

2778891556608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26572 (or 26549 counting only the distinct ones).

The product of its (nonzero) digits is 406425600, while the sum is 72.

The spelling of 2778891556608 in words is "two trillion, seven hundred seventy-eight billion, eight hundred ninety-one million, five hundred fifty-six thousand, six hundred eight".