27999997 has 4 divisors (see below), whose sum is σ = 28031776. Its totient is φ = 27968220.

The previous prime is 27999943. The next prime is 28000019. The reversal of 27999997 is 79999972.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 27999997 - 2⁷ = 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 (27999397) 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, 14529 + ... + 16342.

It is an arithmetic number, because the mean of its divisors is an integer number (7007944).

Almost surely, 2^27999997 is an apocalyptic number.

It is an amenable number.

27999997 is a deficient number, since it is larger than the sum of its proper divisors (31779).

27999997 is an equidigital number, since it uses as much as digits as its factorization.

27999997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31778.

The product of its digits is 5786802, while the sum is 61.

The square root of 27999997 is about 5291.5023386558. The cubic root of 27999997 is about 303.6588863426.

The spelling of 27999997 in words is "twenty-seven million, nine hundred ninety-nine thousand, nine hundred ninety-seven".