64978905600 has 720 divisors, whose sum is σ = 279815215680. Its totient is φ = 14067302400.

The previous prime is 64978905587. The next prime is 64978905631. The reversal of 64978905600 is 650987946.

64978905600 is a `hidden beast` number, since 6 + 4 + 9 + 78 + 9 + 0 + 560 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

It is a super-2 number, since 2×64978905600² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 15319480 + ... + 15323720.

It is an arithmetic number, because the mean of its divisors is an integer number (388632244).

Almost surely, 2^64978905600 is an apocalyptic number.

64978905600 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 64978905600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139907607840).

64978905600 is an abundant number, since it is smaller than the sum of its proper divisors (214836310080).

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

64978905600 is a wasteful number, since it uses less digits than its factorization.

64978905600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4301 (or 4277 counting only the distinct ones).

The product of its (nonzero) digits is 3265920, while the sum is 54.

The spelling of 64978905600 in words is "sixty-four billion, nine hundred seventy-eight million, nine hundred five thousand, six hundred".