64897597440 has 960 divisors, whose sum is σ = 259388814720. Its totient is φ = 15288238080.

The previous prime is 64897597397. The next prime is 64897597441. The reversal of 64897597440 is 4479579846.

64897597440 is a `hidden beast` number, since 64 + 89 + 7 + 59 + 7 + 440 = 666.

It is a tau number, because it is divible by the number of its divisors (960).

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (64897597441) 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, 1063895010 + ... + 1063895070.

It is an arithmetic number, because the mean of its divisors is an integer number (270196682).

Almost surely, 2^64897597440 is an apocalyptic number.

64897597440 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 64897597440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129694407360).

64897597440 is an abundant number, since it is smaller than the sum of its proper divisors (194491217280).

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

64897597440 is a wasteful number, since it uses less digits than its factorization.

64897597440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153 (or 121 counting only the distinct ones).

The product of its (nonzero) digits is 60963840, while the sum is 63.

The spelling of 64897597440 in words is "sixty-four billion, eight hundred ninety-seven million, five hundred ninety-seven thousand, four hundred forty".