64168957440 has 720 divisors, whose sum is σ = 261324711648. Its totient is φ = 14508490752.

The previous prime is 64168957403. The next prime is 64168957441. The reversal of 64168957440 is 4475986146.

64168957440 is a `hidden beast` number, since 6 + 4 + 1 + 68 + 9 + 574 + 4 + 0 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64168957441) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 127572229 + ... + 127572731.

Almost surely, 2^64168957440 is an apocalyptic number.

64168957440 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 64168957440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130662355824).

64168957440 is an abundant number, since it is smaller than the sum of its proper divisors (197155754208).

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

64168957440 is a wasteful number, since it uses less digits than its factorization.

64168957440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659 (or 633 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 54.

The spelling of 64168957440 in words is "sixty-four billion, one hundred sixty-eight million, nine hundred fifty-seven thousand, four hundred forty".