27991808409619 has 2 divisors, whose sum is σ = 27991808409620. Its totient is φ = 27991808409618.

The previous prime is 27991808409557. The next prime is 27991808409647. The reversal of 27991808409619 is 91690480819972.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 27991808409619 - 2³⁹ = 27442052595731 is a prime.

It is a super-2 number, since 2×27991808409619² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (27991808409919) 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, 13995904204809 + 13995904204810.

It is an arithmetic number, because the mean of its divisors is an integer number (13995904204810).

Almost surely, 2^{27991808409619} is an apocalyptic number.

27991808409619 is a deficient number, since it is larger than the sum of its proper divisors (1).

27991808409619 is an equidigital number, since it uses as much as digits as its factorization.

27991808409619 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 141087744, while the sum is 73.

The spelling of 27991808409619 in words is "twenty-seven trillion, nine hundred ninety-one billion, eight hundred eight million, four hundred nine thousand, six hundred nineteen".