2780320840 has 64 divisors (see below), whose sum is σ = 6901200000. Its totient is φ = 999651840.

The previous prime is 2780320793. The next prime is 2780320843. The reversal of 2780320840 is 480230872.

It is a junction number, because it is equal to n+sod(n) for n = 2780320796 and 2780320805.

It is not an unprimeable number, because it can be changed into a prime (2780320843) 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 15 ways as a sum of consecutive naturals, for example, 3661 + ... + 74659.

It is an arithmetic number, because the mean of its divisors is an integer number (107831250).

Almost surely, 2^2780320840 is an apocalyptic number.

2780320840 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 2780320840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3450600000).

2780320840 is an abundant number, since it is smaller than the sum of its proper divisors (4120879160).

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

2780320840 is a wasteful number, since it uses less digits than its factorization.

2780320840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71110 (or 71106 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 34.

The square root of 2780320840 is about 52728.7477567977. The cubic root of 2780320840 is about 1406.1499583416.

The spelling of 2780320840 in words is "two billion, seven hundred eighty million, three hundred twenty thousand, eight hundred forty".