2561286600 has 72 divisors (see below), whose sum is σ = 8601660210. Its totient is φ = 683009280.

The previous prime is 2561286593. The next prime is 2561286643. The reversal of 2561286600 is 66821652.

2561286600 is a `hidden beast` number, since 25 + 6 + 1 + 28 + 6 + 600 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 2436607044 + 124679556 = 49362^2 + 11166^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 709669 + ... + 713268.

Almost surely, 2^2561286600 is an apocalyptic number.

2561286600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2561286600 is an abundant number, since it is smaller than the sum of its proper divisors (6040373610).

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

2561286600 is a wasteful number, since it uses less digits than its factorization.

2561286600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1422959 (or 1422947 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 2561286600 is about 50609.1552982264. The cubic root of 2561286600 is about 1368.2098913611.

The spelling of 2561286600 in words is "two billion, five hundred sixty-one million, two hundred eighty-six thousand, six hundred".