2561561512 has 32 divisors (see below), whose sum is σ = 4848237000. Its totient is φ = 1268745984.

The previous prime is 2561561507. The next prime is 2561561531. The reversal of 2561561512 is 2151651652.

It can be written as a sum of positive squares in 4 ways, for example, as 1563886116 + 997675396 = 39546^2 + 31586^2 .

It is a super-2 number, since 2×2561561512² = 13123194759519452288, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 470518 + ... + 475930.

Almost surely, 2^2561561512 is an apocalyptic number.

It is an amenable number.

2561561512 is a deficient number, since it is larger than the sum of its proper divisors (2286675488).

2561561512 is a wasteful number, since it uses less digits than its factorization.

2561561512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5965 (or 5961 counting only the distinct ones).

The product of its digits is 18000, while the sum is 34.

The square root of 2561561512 is about 50611.8712556649. The cubic root of 2561561512 is about 1368.2588412210.

The spelling of 2561561512 in words is "two billion, five hundred sixty-one million, five hundred sixty-one thousand, five hundred twelve".