27405138979 has 4 divisors (see below), whose sum is σ = 27869632920. Its totient is φ = 26940645040.

The previous prime is 27405138967. The next prime is 27405138989. The reversal of 27405138979 is 97983150472.

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 27405138979 - 2³¹ = 25257655331 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27405138989) 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, 232246882 + ... + 232246999.

It is an arithmetic number, because the mean of its divisors is an integer number (6967408230).

Almost surely, 2^27405138979 is an apocalyptic number.

27405138979 is a deficient number, since it is larger than the sum of its proper divisors (464493941).

27405138979 is an equidigital number, since it uses as much as digits as its factorization.

27405138979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 464493940.

The product of its (nonzero) digits is 3810240, while the sum is 55.

The spelling of 27405138979 in words is "twenty-seven billion, four hundred five million, one hundred thirty-eight thousand, nine hundred seventy-nine".