27115991 has 4 divisors (see below), whose sum is σ = 30989712. Its totient is φ = 23242272.

The previous prime is 27115973. The next prime is 27115993. The reversal of 27115991 is 19951172.

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 27115991 - 2⁶ = 27115927 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 (27115993) 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, 1936850 + ... + 1936863.

It is an arithmetic number, because the mean of its divisors is an integer number (7747428).

Almost surely, 2^27115991 is an apocalyptic number.

27115991 is a deficient number, since it is larger than the sum of its proper divisors (3873721).

27115991 is an equidigital number, since it uses as much as digits as its factorization.

27115991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3873720.

The product of its digits is 5670, while the sum is 35.

The square root of 27115991 is about 5207.3017004971. The cubic root of 27115991 is about 300.4289825837.

The spelling of 27115991 in words is "twenty-seven million, one hundred fifteen thousand, nine hundred ninety-one".