2780456 has 48 divisors (see below), whose sum is σ = 6248340. Its totient is φ = 1155840.

The previous prime is 2780443. The next prime is 2780467. The reversal of 2780456 is 6540872.

It can be written as a sum of positive squares in 2 ways, for example, as 2775556 + 4900 = 1666^2 + 70^2 .

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15986 + ... + 16158.

2^2780456 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 2780456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3124170).

2780456 is an abundant number, since it is smaller than the sum of its proper divisors (3467884).

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

2780456 is a wasteful number, since it uses less digits than its factorization.

2780456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234 (or 223 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 32.

The square root of 2780456 is about 1667.4699397590. The cubic root of 2780456 is about 140.6172743739.

The spelling of 2780456 in words is "two million, seven hundred eighty thousand, four hundred fifty-six".