2561123560 has 16 divisors (see below), whose sum is σ = 5762528100. Its totient is φ = 1024449408.

The previous prime is 2561123549. The next prime is 2561123567. The reversal of 2561123560 is 653211652.

It can be written as a sum of positive squares in 2 ways, for example, as 2375782564 + 185340996 = 48742^2 + 13614^2 .

It is not an unprimeable number, because it can be changed into a prime (2561123567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32014005 + ... + 32014084.

Almost surely, 2^2561123560 is an apocalyptic number.

2561123560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2561123560 is an abundant number, since it is smaller than the sum of its proper divisors (3201404540).

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

2561123560 is a wasteful number, since it uses less digits than its factorization.

2561123560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64028100 (or 64028096 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 2561123560 is about 50607.5444968436. The cubic root of 2561123560 is about 1368.1808593798.

The spelling of 2561123560 in words is "two billion, five hundred sixty-one million, one hundred twenty-three thousand, five hundred sixty".