27978069709 has 4 divisors (see below), whose sum is σ = 28239547104. Its totient is φ = 27716592316.

The previous prime is 27978069683. The next prime is 27978069727. The reversal of 27978069709 is 90796087972.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 27978069709 - 2¹⁵ = 27978036941 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 (27978069799) 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, 130738537 + ... + 130738750.

It is an arithmetic number, because the mean of its divisors is an integer number (7059886776).

Almost surely, 2^27978069709 is an apocalyptic number.

It is an amenable number.

27978069709 is a deficient number, since it is larger than the sum of its proper divisors (261477395).

27978069709 is a wasteful number, since it uses less digits than its factorization.

27978069709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 261477394.

The product of its (nonzero) digits is 24004512, while the sum is 64.

The spelling of 27978069709 in words is "twenty-seven billion, nine hundred seventy-eight million, sixty-nine thousand, seven hundred nine".