646646365798272 has 1536 divisors, whose sum is σ = 2352977149248000. Its totient is φ = 174020777312256.

The previous prime is 646646365798183. The next prime is 646646365798309. The reversal of 646646365798272 is 272897563646646.

646646365798272 is a `hidden beast` number, since 6 + 4 + 6 + 6 + 4 + 6 + 36 + 579 + 8 + 2 + 7 + 2 = 666.

It is a super-2 number, since 2×646646365798272² (a number of 30 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 646646365798191 and 646646365798200.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 245592997468 + ... + 245593000100.

It is an arithmetic number, because the mean of its divisors is an integer number (1531886164875).

Almost surely, 2^{646646365798272} 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 646646365798272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1176488574624000).

646646365798272 is an abundant number, since it is smaller than the sum of its proper divisors (1706330783449728).

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

646646365798272 is a wasteful number, since it uses less digits than its factorization.

646646365798272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3905 (or 3880 counting only the distinct ones).

The product of its digits is 26336378880, while the sum is 81.

The spelling of 646646365798272 in words is "six hundred forty-six trillion, six hundred forty-six billion, three hundred sixty-five million, seven hundred ninety-eight thousand, two hundred seventy-two".