27999871 has 4 divisors (see below), whose sum is σ = 28017144. Its totient is φ = 27982600.

The previous prime is 27999869. The next prime is 27999883. The reversal of 27999871 is 17899972.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 27999871 - 2¹ = 27999869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27999841) 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, 5920 + ... + 9541.

It is an arithmetic number, because the mean of its divisors is an integer number (7004286).

Almost surely, 2^27999871 is an apocalyptic number.

27999871 is a deficient number, since it is larger than the sum of its proper divisors (17273).

27999871 is a wasteful number, since it uses less digits than its factorization.

27999871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17272.

The product of its digits is 571536, while the sum is 52.

The square root of 27999871 is about 5291.4904327609. The cubic root of 27999871 is about 303.6584308535.

The spelling of 27999871 in words is "twenty-seven million, nine hundred ninety-nine thousand, eight hundred seventy-one".