27643920645 has 64 divisors (see below), whose sum is σ = 49307056128. Its totient is φ = 13112736000.

The previous prime is 27643920631. The next prime is 27643920671. The reversal of 27643920645 is 54602934672.

It is not a de Polignac number, because 27643920645 - 2⁵ = 27643920613 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 27643920594 and 27643920603.

It is a congruent number.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 1525659 + ... + 1543671.

It is an arithmetic number, because the mean of its divisors is an integer number (770422752).

Almost surely, 2^27643920645 is an apocalyptic number.

It is an amenable number.

27643920645 is a deficient number, since it is larger than the sum of its proper divisors (21663135483).

27643920645 is a wasteful number, since it uses less digits than its factorization.

27643920645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18234.

The product of its (nonzero) digits is 2177280, while the sum is 48.

The spelling of 27643920645 in words is "twenty-seven billion, six hundred forty-three million, nine hundred twenty thousand, six hundred forty-five".