2780347440 has 160 divisors (see below), whose sum is σ = 9338777280. Its totient is φ = 684263424.

The previous prime is 2780347337. The next prime is 2780347457. The reversal of 2780347440 is 447430872.

It is a Cunningham number, because it is equal to 52729²-1.

It is a super-2 number, since 2×2780347440² = 15460663774229107200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 524644 + ... + 529916.

It is an arithmetic number, because the mean of its divisors is an integer number (58367358).

Almost surely, 2^2780347440 is an apocalyptic number.

2780347440 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 2780347440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4669388640).

2780347440 is an abundant number, since it is smaller than the sum of its proper divisors (6558429840).

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

2780347440 is a wasteful number, since it uses less digits than its factorization.

2780347440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5328 (or 5296 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 39.

The square root of 2780347440 is about 52728.9999905176. Note that the first 5 decimals coincide. The cubic root of 2780347440 is about 1406.1544426525.

The spelling of 2780347440 in words is "two billion, seven hundred eighty million, three hundred forty-seven thousand, four hundred forty".