27961161 has 4 divisors (see below), whose sum is σ = 37281552. Its totient is φ = 18640772.

The previous prime is 27961121. The next prime is 27961187. The reversal of 27961161 is 16116972.

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 27961161 - 2⁶ = 27961097 is a prime.

It is not an unprimeable number, because it can be changed into a prime (27961111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4660191 + ... + 4660196.

It is an arithmetic number, because the mean of its divisors is an integer number (9320388).

Almost surely, 2^27961161 is an apocalyptic number.

It is an amenable number.

27961161 is a deficient number, since it is larger than the sum of its proper divisors (9320391).

27961161 is an equidigital number, since it uses as much as digits as its factorization.

27961161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9320390.

The product of its digits is 4536, while the sum is 33.

The square root of 27961161 is about 5287.8314080538. The cubic root of 27961161 is about 303.5184297446.

The spelling of 27961161 in words is "twenty-seven million, nine hundred sixty-one thousand, one hundred sixty-one".