64249975440 has 640 divisors, whose sum is σ = 269472752640. Its totient is φ = 13735526400.

The previous prime is 64249975429. The next prime is 64249975477. The reversal of 64249975440 is 4457994246.

64249975440 is a `hidden beast` number, since 6 + 4 + 2 + 4 + 9 + 97 + 544 + 0 = 666.

64249975440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

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, 46523550 + ... + 46524930.

It is an arithmetic number, because the mean of its divisors is an integer number (421051176).

Almost surely, 2^64249975440 is an apocalyptic number.

64249975440 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 64249975440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134736376320).

64249975440 is an abundant number, since it is smaller than the sum of its proper divisors (205222777200).

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

64249975440 is a wasteful number, since it uses less digits than its factorization.

64249975440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1608 (or 1596 counting only the distinct ones).

The product of its (nonzero) digits is 8709120, while the sum is 54.

The spelling of 64249975440 in words is "sixty-four billion, two hundred forty-nine million, nine hundred seventy-five thousand, four hundred forty".