6439713840 has 480 divisors, whose sum is σ = 26344980480. Its totient is φ = 1431032832.

The previous prime is 6439713827. The next prime is 6439713853. The reversal of 6439713840 is 483179346.

It is an interprime number because it is at equal distance from previous prime (6439713827) and next prime (6439713853).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 5034321 + ... + 5035599.

It is an arithmetic number, because the mean of its divisors is an integer number (54885376).

Almost surely, 2^6439713840 is an apocalyptic number.

6439713840 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 6439713840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13172490240).

6439713840 is an abundant number, since it is smaller than the sum of its proper divisors (19905266640).

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

6439713840 is a wasteful number, since it uses less digits than its factorization.

6439713840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1351 (or 1333 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The square root of 6439713840 is about 80247.8276341485. The cubic root of 6439713840 is about 1860.4679363776.

The spelling of 6439713840 in words is "six billion, four hundred thirty-nine million, seven hundred thirteen thousand, eight hundred forty".