6449555520 has 168 divisors, whose sum is σ = 22344766080. Its totient is φ = 1707402240.

The previous prime is 6449555503. The next prime is 6449555521. The reversal of 6449555520 is 255559446.

6449555520 is a `hidden beast` number, since 6 + 4 + 4 + 95 + 5 + 552 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (6449555521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 392265 + ... + 408375.

It is an arithmetic number, because the mean of its divisors is an integer number (133004560).

Almost surely, 2^6449555520 is an apocalyptic number.

6449555520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6449555520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11172383040).

6449555520 is an abundant number, since it is smaller than the sum of its proper divisors (15895210560).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6449555520 is a wasteful number, since it uses less digits than its factorization.

6449555520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16273 (or 16260 counting only the distinct ones).

The product of its (nonzero) digits is 1080000, while the sum is 45.

The square root of 6449555520 is about 80309.1247617604. The cubic root of 6449555520 is about 1861.4152253816.

The spelling of 6449555520 in words is "six billion, four hundred forty-nine million, five hundred fifty-five thousand, five hundred twenty".