64777181616 has 120 divisors (see below), whose sum is σ = 219371521824. Its totient is φ = 17419069440.

The previous prime is 64777181597. The next prime is 64777181659. The reversal of 64777181616 is 61618177746.

It is a happy number.

64777181616 is a `hidden beast` number, since 6 + 4 + 7 + 7 + 7 + 18 + 1 + 616 = 666.

It is a super-2 number, since 2×64777181616² (a number of 22 digits) contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1872955 + ... + 1907226.

Almost surely, 2^64777181616 is an apocalyptic number.

It is an amenable number.

64777181616 is an abundant number, since it is smaller than the sum of its proper divisors (154594340208).

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

64777181616 is a wasteful number, since it uses less digits than its factorization.

64777181616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3780219 (or 3780210 counting only the distinct ones).

The product of its digits is 2370816, while the sum is 54.

The spelling of 64777181616 in words is "sixty-four billion, seven hundred seventy-seven million, one hundred eighty-one thousand, six hundred sixteen".