64449544320 has 1024 divisors, whose sum is σ = 284359680000. Its totient is φ = 13460815872.

The previous prime is 64449544319. The next prime is 64449544399. The reversal of 64449544320 is 2344594446.

64449544320 is a `hidden beast` number, since 6 + 44 + 49 + 544 + 3 + 20 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 66648477 + ... + 66649443.

It is an arithmetic number, because the mean of its divisors is an integer number (277695000).

Almost surely, 2^64449544320 is an apocalyptic number.

64449544320 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 64449544320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142179840000).

64449544320 is an abundant number, since it is smaller than the sum of its proper divisors (219910135680).

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

64449544320 is a wasteful number, since it uses less digits than its factorization.

64449544320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1050 (or 1032 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 45.

The spelling of 64449544320 in words is "sixty-four billion, four hundred forty-nine million, five hundred forty-four thousand, three hundred twenty".