27999869 has 2 divisors, whose sum is σ = 27999870. Its totient is φ = 27999868.

The previous prime is 27999857. The next prime is 27999883. The reversal of 27999869 is 96899972.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27931225 + 68644 = 5285^2 + 262^2 .

It is a cyclic number.

It is not a de Polignac number, because 27999869 - 2⁸ = 27999613 is a prime.

It is a super-2 number, since 2×27999869² = 1567985328034322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27999899) 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, 13999934 + 13999935.

It is an arithmetic number, because the mean of its divisors is an integer number (13999935).

Almost surely, 2^27999869 is an apocalyptic number.

It is an amenable number.

27999869 is a deficient number, since it is larger than the sum of its proper divisors (1).

27999869 is an equidigital number, since it uses as much as digits as its factorization.

27999869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4408992, while the sum is 59.

The square root of 27999869 is about 5291.4902437782. The cubic root of 27999869 is about 303.6584236235.

The spelling of 27999869 in words is "twenty-seven million, nine hundred ninety-nine thousand, eight hundred sixty-nine".