27981487 has 2 divisors, whose sum is σ = 27981488. Its totient is φ = 27981486.

The previous prime is 27981467. The next prime is 27981521. The reversal of 27981487 is 78418972.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 27981487 - 2²³ = 19592879 is a prime.

It is a super-2 number, since 2×27981487² = 1565927229462338, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27981407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13990743 + 13990744.

It is an arithmetic number, because the mean of its divisors is an integer number (13990744).

Almost surely, 2^27981487 is an apocalyptic number.

27981487 is a deficient number, since it is larger than the sum of its proper divisors (1).

27981487 is an equidigital number, since it uses as much as digits as its factorization.

27981487 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 225792, while the sum is 46.

The square root of 27981487 is about 5289.7530188091. The cubic root of 27981487 is about 303.5919581806.

The spelling of 27981487 in words is "twenty-seven million, nine hundred eighty-one thousand, four hundred eighty-seven".