64565557056 has 896 divisors, whose sum is σ = 257534054400. Its totient is φ = 15318097920.

The previous prime is 64565557039. The next prime is 64565557073. The reversal of 64565557056 is 65075556546.

64565557056 is a `hidden beast` number, since 6 + 4 + 5 + 65 + 5 + 570 + 5 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (64565557039) and next prime (64565557073).

It is a super-2 number, since 2×64565557056² (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 junction number, because it is equal to n+sod(n) for n = 64565556993 and 64565557011.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 281945550 + ... + 281945778.

It is an arithmetic number, because the mean of its divisors is an integer number (287426400).

Almost surely, 2^64565557056 is an apocalyptic number.

64565557056 is a gapful number since it is divisible by the number (66) 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 64565557056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (128767027200).

64565557056 is an abundant number, since it is smaller than the sum of its proper divisors (192968497344).

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

64565557056 is a wasteful number, since it uses less digits than its factorization.

64565557056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 444 (or 428 counting only the distinct ones).

The product of its (nonzero) digits is 18900000, while the sum is 54.

The spelling of 64565557056 in words is "sixty-four billion, five hundred sixty-five million, five hundred fifty-seven thousand, fifty-six".