64005583440 has 320 divisors, whose sum is σ = 218578010112. Its totient is φ = 15423283200.

The previous prime is 64005583429. The next prime is 64005583441. The reversal of 64005583440 is 4438550046.

64005583440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×64005583440² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64005583441) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 16566949 + ... + 16570811.

Almost surely, 2^64005583440 is an apocalyptic number.

64005583440 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 64005583440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109289005056).

64005583440 is an abundant number, since it is smaller than the sum of its proper divisors (154572426672).

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

64005583440 is a wasteful number, since it uses less digits than its factorization.

64005583440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4058 (or 4052 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 39.

The spelling of 64005583440 in words is "sixty-four billion, five million, five hundred eighty-three thousand, four hundred forty".