64909839240 has 224 divisors, whose sum is σ = 221977413720. Its totient is φ = 17071617024.

The previous prime is 64909839217. The next prime is 64909839287. The reversal of 64909839240 is 4293890946.

It can be written as a sum of positive squares in 4 ways, for example, as 38191321476 + 26718517764 = 195426^2 + 163458^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

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 55 ways as a sum of consecutive naturals, for example, 2113434 + ... + 2143926.

Almost surely, 2^64909839240 is an apocalyptic number.

64909839240 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 64909839240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110988706860).

64909839240 is an abundant number, since it is smaller than the sum of its proper divisors (157067574480).

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

64909839240 is a wasteful number, since it uses less digits than its factorization.

64909839240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30595 (or 30576 counting only the distinct ones).

The product of its (nonzero) digits is 3359232, while the sum is 54.

The spelling of 64909839240 in words is "sixty-four billion, nine hundred nine million, eight hundred thirty-nine thousand, two hundred forty".