7782778080 has 720 divisors, whose sum is σ = 34552314720. Its totient is φ = 1614919680.

The previous prime is 7782778049. The next prime is 7782778099. The reversal of 7782778080 is 808772877.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

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 119 ways as a sum of consecutive naturals, for example, 10976766 + ... + 10977474.

It is an arithmetic number, because the mean of its divisors is an integer number (47989326).

Almost surely, 2^7782778080 is an apocalyptic number.

7782778080 is a gapful number since it is divisible by the number (70) 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 7782778080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17276157360).

7782778080 is an abundant number, since it is smaller than the sum of its proper divisors (26769536640).

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

7782778080 is a wasteful number, since it uses less digits than its factorization.

7782778080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 765 (or 737 counting only the distinct ones).

The product of its (nonzero) digits is 2458624, while the sum is 54.

The square root of 7782778080 is about 88220.0548628258. The cubic root of 7782778080 is about 1981.7318181472.

The spelling of 7782778080 in words is "seven billion, seven hundred eighty-two million, seven hundred seventy-eight thousand, eighty".