64138507776 has 320 divisors, whose sum is σ = 217581788160. Its totient is φ = 18274222080.

The previous prime is 64138507759. The next prime is 64138507877. The reversal of 64138507776 is 67770583146.

64138507776 is a `hidden beast` number, since 64 + 1 + 3 + 8 + 507 + 7 + 76 = 666.

It is a super-2 number, since 2×64138507776² (a number of 22 digits) contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 47125336 + ... + 47126696.

It is an arithmetic number, because the mean of its divisors is an integer number (679943088).

Almost surely, 2^64138507776 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64138507776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108790894080).

64138507776 is an abundant number, since it is smaller than the sum of its proper divisors (153443280384).

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

64138507776 is a wasteful number, since it uses less digits than its factorization.

64138507776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1882 (or 1860 counting only the distinct ones).

The product of its (nonzero) digits is 5927040, while the sum is 54.

The spelling of 64138507776 in words is "sixty-four billion, one hundred thirty-eight million, five hundred seven thousand, seven hundred seventy-six".