6445949985 has 24 divisors (see below), whose sum is σ = 11658763584. Its totient is φ = 3288368160.

The previous prime is 6445949981. The next prime is 6445949989. The reversal of 6445949985 is 5899495446.

6445949985 is a `hidden beast` number, since 64 + 4 + 5 + 9 + 499 + 85 = 666.

It is an interprime number because it is at equal distance from previous prime (6445949981) and next prime (6445949989).

It is not a de Polignac number, because 6445949985 - 2² = 6445949981 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6445949981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3112951 + ... + 3115020.

It is an arithmetic number, because the mean of its divisors is an integer number (485781816).

Almost surely, 2^6445949985 is an apocalyptic number.

It is an amenable number.

6445949985 is a deficient number, since it is larger than the sum of its proper divisors (5212813599).

6445949985 is a wasteful number, since it uses less digits than its factorization.

6445949985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6228005 (or 6228002 counting only the distinct ones).

The product of its digits is 55987200, while the sum is 63.

The square root of 6445949985 is about 80286.6737696861. The cubic root of 6445949985 is about 1861.0682945608.

The spelling of 6445949985 in words is "six billion, four hundred forty-five million, nine hundred forty-nine thousand, nine hundred eighty-five".