6640444445 has 16 divisors (see below), whose sum is σ = 8144478720. Its totient is φ = 5196033600.

The previous prime is 6640444439. The next prime is 6640444457. The reversal of 6640444445 is 5444440466.

It is a happy number.

It is not a de Polignac number, because 6640444445 - 2⁴ = 6640444429 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6221 + ... + 115410.

It is an arithmetic number, because the mean of its divisors is an integer number (509029920).

Almost surely, 2^6640444445 is an apocalyptic number.

It is an amenable number.

6640444445 is a deficient number, since it is larger than the sum of its proper divisors (1504034275).

6640444445 is a wasteful number, since it uses less digits than its factorization.

6640444445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121876.

The product of its (nonzero) digits is 737280, while the sum is 41.

The square root of 6640444445 is about 81488.9222225942. The cubic root of 6640444445 is about 1879.6012098342.

The spelling of 6640444445 in words is "six billion, six hundred forty million, four hundred forty-four thousand, four hundred forty-five".