27561561540 has 24 divisors (see below), whose sum is σ = 77172372480. Its totient is φ = 7349749728.

The previous prime is 27561561451. The next prime is 27561561637. The reversal of 27561561540 is 4516516572.

It is a junction number, because it is equal to n+sod(n) for n = 27561561492 and 27561561501.

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, 229679620 + ... + 229679739.

It is an arithmetic number, because the mean of its divisors is an integer number (3215515520).

Almost surely, 2^27561561540 is an apocalyptic number.

27561561540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

27561561540 is an abundant number, since it is smaller than the sum of its proper divisors (49610810940).

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

27561561540 is a wasteful number, since it uses less digits than its factorization.

27561561540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 459359371 (or 459359369 counting only the distinct ones).

The product of its (nonzero) digits is 252000, while the sum is 42.

The spelling of 27561561540 in words is "twenty-seven billion, five hundred sixty-one million, five hundred sixty-one thousand, five hundred forty".