2556720 has 120 divisors (see below), whose sum is σ = 8878896. Its totient is φ = 658944.

The previous prime is 2556713. The next prime is 2556739. The reversal of 2556720 is 276552.

It is a tau number, because it is divible by the number of its divisors (120).

It is an Ulam number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38127 + ... + 38193.

2^2556720 is an apocalyptic number.

2556720 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 2556720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4439448).

2556720 is an abundant number, since it is smaller than the sum of its proper divisors (6322176).

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

2556720 is a wasteful number, since it uses less digits than its factorization.

2556720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139 (or 130 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 27.

The square root of 2556720 is about 1598.9746714692. The cubic root of 2556720 is about 136.7396265862.

The spelling of 2556720 in words is "two million, five hundred fifty-six thousand, seven hundred twenty".