27991352863 has 4 divisors (see below), whose sum is σ = 28003691560. Its totient is φ = 27979014168.

The previous prime is 27991352861. The next prime is 27991352869. The reversal of 27991352863 is 36825319972.

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

It is a cyclic number.

It is not a de Polignac number, because 27991352863 - 2¹ = 27991352861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27991352861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6165945 + ... + 6170482.

It is an arithmetic number, because the mean of its divisors is an integer number (7000922890).

Almost surely, 2^27991352863 is an apocalyptic number.

27991352863 is a deficient number, since it is larger than the sum of its proper divisors (12338697).

27991352863 is a wasteful number, since it uses less digits than its factorization.

27991352863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12338696.

The product of its digits is 4898880, while the sum is 55.

The spelling of 27991352863 in words is "twenty-seven billion, nine hundred ninety-one million, three hundred fifty-two thousand, eight hundred sixty-three".