27918820819 has 2 divisors, whose sum is σ = 27918820820. Its totient is φ = 27918820818.

The previous prime is 27918820817. The next prime is 27918820847. The reversal of 27918820819 is 91802881972.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 27918820819 - 2¹ = 27918820817 is a prime.

It is a super-2 number, since 2×27918820819² (a number of 22 digits) contains 22 as substring.

Together with 27918820817, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 27918820819.

It is not a weakly prime, because it can be changed into another prime (27918820817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13959410409 + 13959410410.

It is an arithmetic number, because the mean of its divisors is an integer number (13959410410).

Almost surely, 2^27918820819 is an apocalyptic number.

27918820819 is a deficient number, since it is larger than the sum of its proper divisors (1).

27918820819 is an equidigital number, since it uses as much as digits as its factorization.

27918820819 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1161216, while the sum is 55.

The spelling of 27918820819 in words is "twenty-seven billion, nine hundred eighteen million, eight hundred twenty thousand, eight hundred nineteen".