27861284889 has 9 divisors (see below), whose sum is σ = 40244801493. Its totient is φ = 18573856092.

The previous prime is 27861284849. The next prime is 27861284903. The reversal of 27861284889 is 98848216872.

The square root of 27861284889 is 166917.

It is a perfect power (a square), and thus also a powerful number.

27861284889 is a `hidden beast` number, since 2 + 7 + 8 + 612 + 8 + 4 + 8 + 8 + 9 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 27861284889 - 2¹⁹ = 27860760601 is a prime.

It is not an unprimeable number, because it can be changed into a prime (27861284839) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 472932 + ... + 528570.

Almost surely, 2^27861284889 is an apocalyptic number.

27861284889 is the 166917-th square number.

27861284889 is the 83459-th centered octagonal number.

It is an amenable number.

27861284889 is a deficient number, since it is larger than the sum of its proper divisors (12383516604).

27861284889 is an frugal number, since it uses more digits than its factorization.

27861284889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111284 (or 55642 counting only the distinct ones).

The product of its digits is 24772608, while the sum is 63.

The spelling of 27861284889 in words is "twenty-seven billion, eight hundred sixty-one million, two hundred eighty-four thousand, eight hundred eighty-nine".