646829438976 has 384 divisors, whose sum is σ = 2318621760000. Its totient is φ = 173935558656.

The previous prime is 646829438947. The next prime is 646829438989. The reversal of 646829438976 is 679834928646.

646829438976 is a `hidden beast` number, since 6 + 46 + 82 + 9 + 438 + 9 + 76 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (72).

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

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, 6531075 + ... + 6629373.

It is an arithmetic number, because the mean of its divisors is an integer number (6038077500).

Almost surely, 2^646829438976 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 646829438976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1159310880000).

646829438976 is an abundant number, since it is smaller than the sum of its proper divisors (1671792321024).

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

646829438976 is a wasteful number, since it uses less digits than its factorization.

646829438976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98354 (or 98328 counting only the distinct ones).

The product of its digits is 752467968, while the sum is 72.

The spelling of 646829438976 in words is "six hundred forty-six billion, eight hundred twenty-nine million, four hundred thirty-eight thousand, nine hundred seventy-six".