27728746639 has 32 divisors (see below), whose sum is σ = 31593196800. Its totient is φ = 24117730560.

The previous prime is 27728746589. The next prime is 27728746657. The reversal of 27728746639 is 93664782772.

It is a happy number.

It is not a de Polignac number, because 27728746639 - 2⁷ = 27728746511 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27728746739) 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 31 ways as a sum of consecutive naturals, for example, 4585552 + ... + 4591594.

It is an arithmetic number, because the mean of its divisors is an integer number (987287400).

Almost surely, 2^27728746639 is an apocalyptic number.

27728746639 is a deficient number, since it is larger than the sum of its proper divisors (3864450161).

27728746639 is a wasteful number, since it uses less digits than its factorization.

27728746639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6295.

The product of its digits is 42674688, while the sum is 61.

The spelling of 27728746639 in words is "twenty-seven billion, seven hundred twenty-eight million, seven hundred forty-six thousand, six hundred thirty-nine".