27768351865 has 4 divisors (see below), whose sum is σ = 33322022244. Its totient is φ = 22214681488.

The previous prime is 27768351839. The next prime is 27768351883. The reversal of 27768351865 is 56815386772.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8651418169 + 19116933696 = 93013^2 + 138264^2 .

It is a cyclic number.

It is not a de Polignac number, because 27768351865 - 2⁵ = 27768351833 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2776835182 + ... + 2776835191.

It is an arithmetic number, because the mean of its divisors is an integer number (8330505561).

Almost surely, 2^27768351865 is an apocalyptic number.

It is an amenable number.

27768351865 is a deficient number, since it is larger than the sum of its proper divisors (5553670379).

27768351865 is an equidigital number, since it uses as much as digits as its factorization.

27768351865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5553670378.

The product of its digits is 16934400, while the sum is 58.

The spelling of 27768351865 in words is "twenty-seven billion, seven hundred sixty-eight million, three hundred fifty-one thousand, eight hundred sixty-five".