64645727040 has 168 divisors, whose sum is σ = 224323232328. Its totient is φ = 17086218240.

The previous prime is 64645727039. The next prime is 64645727057. The reversal of 64645727040 is 4072754646.

64645727040 is a `hidden beast` number, since 6 + 4 + 6 + 4 + 572 + 70 + 4 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 3312232704 + 61333494336 = 57552^2 + 247656^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

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, 226120 + ... + 424760.

Almost surely, 2^64645727040 is an apocalyptic number.

64645727040 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 64645727040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112161616164).

64645727040 is an abundant number, since it is smaller than the sum of its proper divisors (159677505288).

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

64645727040 is a wasteful number, since it uses less digits than its factorization.

64645727040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198777 (or 198764 counting only the distinct ones).

The product of its (nonzero) digits is 1128960, while the sum is 45.

The spelling of 64645727040 in words is "sixty-four billion, six hundred forty-five million, seven hundred twenty-seven thousand, forty".