6445445851 has 16 divisors (see below), whose sum is σ = 6970163200. Its totient is φ = 5924920608.

The previous prime is 6445445849. The next prime is 6445445857. The reversal of 6445445851 is 1585445446.

It is a cyclic number.

It is not a de Polignac number, because 6445445851 - 2¹ = 6445445849 is a prime.

It is a super-2 number, since 2×6445445851² = 83087544436346228402, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (6445445857) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5929030 + ... + 5930116.

It is an arithmetic number, because the mean of its divisors is an integer number (435635200).

Almost surely, 2^6445445851 is an apocalyptic number.

6445445851 is a deficient number, since it is larger than the sum of its proper divisors (524717349).

6445445851 is a wasteful number, since it uses less digits than its factorization.

6445445851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2578.

The product of its digits is 1536000, while the sum is 46.

The square root of 6445445851 is about 80283.5341212630. The cubic root of 6445445851 is about 1861.0197756062.

The spelling of 6445445851 in words is "six billion, four hundred forty-five million, four hundred forty-five thousand, eight hundred fifty-one".