27813281 has 2 divisors, whose sum is σ = 27813282. Its totient is φ = 27813280.

The previous prime is 27813271. The next prime is 27813299. The reversal of 27813281 is 18231872.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27300625 + 512656 = 5225^2 + 716^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27813281 is a prime.

It is a super-2 number, since 2×27813281² = 1547157199969922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (27813221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13906640 + 13906641.

It is an arithmetic number, because the mean of its divisors is an integer number (13906641).

Almost surely, 2^27813281 is an apocalyptic number.

It is an amenable number.

27813281 is a deficient number, since it is larger than the sum of its proper divisors (1).

27813281 is an equidigital number, since it uses as much as digits as its factorization.

27813281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5376, while the sum is 32.

The square root of 27813281 is about 5273.8298228138. The cubic root of 27813281 is about 302.9824044795.

The spelling of 27813281 in words is "twenty-seven million, eight hundred thirteen thousand, two hundred eighty-one".