66440206404644 has 24 divisors (see below), whose sum is σ = 116333886060000. Its totient is φ = 33201958204800.

The previous prime is 66440206404619. The next prime is 66440206404653. The reversal of 66440206404644 is 44640460204466.

It is a junction number, because it is equal to n+sod(n) for n = 66440206404592 and 66440206404601.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53282252 + ... + 54514940.

It is an arithmetic number, because the mean of its divisors is an integer number (4847245252500).

Almost surely, 2^{66440206404644} is an apocalyptic number.

It is an amenable number.

66440206404644 is a deficient number, since it is larger than the sum of its proper divisors (49893679655356).

66440206404644 is a wasteful number, since it uses less digits than its factorization.

66440206404644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1240043 (or 1240041 counting only the distinct ones).

The product of its (nonzero) digits is 10616832, while the sum is 50.

The spelling of 66440206404644 in words is "sixty-six trillion, four hundred forty billion, two hundred six million, four hundred four thousand, six hundred forty-four".