65669643648 has 256 divisors, whose sum is σ = 224315136000. Its totient is φ = 18524712960.

The previous prime is 65669643643. The next prime is 65669643649. The reversal of 65669643648 is 84634696656.

It is a happy number.

65669643648 is a `hidden beast` number, since 6 + 566 + 9 + 6 + 4 + 3 + 64 + 8 = 666.

65669643648 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65669643643) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1893988 + ... + 1928348.

It is an arithmetic number, because the mean of its divisors is an integer number (876231000).

Almost surely, 2^65669643648 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 65669643648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112157568000).

65669643648 is an abundant number, since it is smaller than the sum of its proper divisors (158645492352).

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

65669643648 is a wasteful number, since it uses less digits than its factorization.

65669643648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34470 (or 34452 counting only the distinct ones).

The product of its digits is 134369280, while the sum is 63.

The spelling of 65669643648 in words is "sixty-five billion, six hundred sixty-nine million, six hundred forty-three thousand, six hundred forty-eight".