2561288280 has 128 divisors (see below), whose sum is σ = 8108812800. Its totient is φ = 645911552.

The previous prime is 2561288239. The next prime is 2561288281. The reversal of 2561288280 is 828821652.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2561288281) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 240427 + ... + 250853.

It is an arithmetic number, because the mean of its divisors is an integer number (63350100).

Almost surely, 2^2561288280 is an apocalyptic number.

2561288280 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 2561288280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4054406400).

2561288280 is an abundant number, since it is smaller than the sum of its proper divisors (5547524520).

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

2561288280 is a wasteful number, since it uses less digits than its factorization.

2561288280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10553 (or 10549 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 42.

The square root of 2561288280 is about 50609.1718960111. The cubic root of 2561288280 is about 1368.2101905066.

The spelling of 2561288280 in words is "two billion, five hundred sixty-one million, two hundred eighty-eight thousand, two hundred eighty".