27971964779 has 4 divisors (see below), whose sum is σ = 30514870680. Its totient is φ = 25429058880.

The previous prime is 27971964767. The next prime is 27971964827. The reversal of 27971964779 is 97746917972.

It is a happy number.

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 27971964779 - 2¹⁶ = 27971899243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27971964079) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1271452934 + ... + 1271452955.

It is an arithmetic number, because the mean of its divisors is an integer number (7628717670).

Almost surely, 2^27971964779 is an apocalyptic number.

27971964779 is a deficient number, since it is larger than the sum of its proper divisors (2542905901).

27971964779 is a wasteful number, since it uses less digits than its factorization.

27971964779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2542905900.

The product of its digits is 84015792, while the sum is 68.

The spelling of 27971964779 in words is "twenty-seven billion, nine hundred seventy-one million, nine hundred sixty-four thousand, seven hundred seventy-nine".