27643920644 has 12 divisors (see below), whose sum is σ = 48392091468. Its totient is φ = 13817608800.

The previous prime is 27643920631. The next prime is 27643920671. The reversal of 27643920644 is 44602934672.

It can be written as a sum of positive squares in 2 ways, for example, as 11796132100 + 15847788544 = 108610^2 + 125888^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1073567 + ... + 1099014.

It is an arithmetic number, because the mean of its divisors is an integer number (4032674289).

Almost surely, 2^27643920644 is an apocalyptic number.

It is an amenable number.

27643920644 is a deficient number, since it is larger than the sum of its proper divisors (20748170824).

27643920644 is a wasteful number, since it uses less digits than its factorization.

27643920644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2175766 (or 2175764 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 47.

The spelling of 27643920644 in words is "twenty-seven billion, six hundred forty-three million, nine hundred twenty thousand, six hundred forty-four".