6390565440 has 224 divisors, whose sum is σ = 23303691264. Its totient is φ = 1453455360.

The previous prime is 6390565439. The next prime is 6390565459. The reversal of 6390565440 is 445650936.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 6390565392 and 6390565401.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1415667 + ... + 1420173.

It is an arithmetic number, because the mean of its divisors is an integer number (104034336).

Almost surely, 2^6390565440 is an apocalyptic number.

6390565440 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 6390565440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11651845632).

6390565440 is an abundant number, since it is smaller than the sum of its proper divisors (16913125824).

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

6390565440 is a wasteful number, since it uses less digits than its factorization.

6390565440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4745 (or 4735 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 42.

The square root of 6390565440 is about 79941.0122527855. The cubic root of 6390565440 is about 1855.7227650217.

The spelling of 6390565440 in words is "six billion, three hundred ninety million, five hundred sixty-five thousand, four hundred forty".