27749643869 has 2 divisors, whose sum is σ = 27749643870. Its totient is φ = 27749643868.

The previous prime is 27749643853. The next prime is 27749643899. The reversal of 27749643869 is 96834694772.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18569512900 + 9180130969 = 136270^2 + 95813^2 .

It is a cyclic number.

It is not a de Polignac number, because 27749643869 - 2⁴ = 27749643853 is a prime.

It is a super-2 number, since 2×27749643869² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27749643809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13874821934 + 13874821935.

It is an arithmetic number, because the mean of its divisors is an integer number (13874821935).

Almost surely, 2^27749643869 is an apocalyptic number.

It is an amenable number.

27749643869 is a deficient number, since it is larger than the sum of its proper divisors (1).

27749643869 is an equidigital number, since it uses as much as digits as its factorization.

27749643869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 109734912, while the sum is 65.

The spelling of 27749643869 in words is "twenty-seven billion, seven hundred forty-nine million, six hundred forty-three thousand, eight hundred sixty-nine".