27731161 has 2 divisors, whose sum is σ = 27731162. Its totient is φ = 27731160.

The previous prime is 27731141. The next prime is 27731177. The reversal of 27731161 is 16113772.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27625536 + 105625 = 5256^2 + 325^2 .

It is a cyclic number.

It is not a de Polignac number, because 27731161 - 2¹⁹ = 27206873 is a prime.

It is not a weakly prime, because it can be changed into another prime (27731101) 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 as a sum of consecutive naturals, namely, 13865580 + 13865581.

It is an arithmetic number, because the mean of its divisors is an integer number (13865581).

Almost surely, 2^27731161 is an apocalyptic number.

It is an amenable number.

27731161 is a deficient number, since it is larger than the sum of its proper divisors (1).

27731161 is an equidigital number, since it uses as much as digits as its factorization.

27731161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1764, while the sum is 28.

The square root of 27731161 is about 5266.0384540943. The cubic root of 27731161 is about 302.6839206646.

It can be divided in two parts, 2773 and 1161, that multiplied together give a triangular number (3219453 = T₂₅₃₇).

The spelling of 27731161 in words is "twenty-seven million, seven hundred thirty-one thousand, one hundred sixty-one".