646783893504 has 816 divisors, whose sum is σ = 2290072512000. Its totient is φ = 175489155072.

The previous prime is 646783893451. The next prime is 646783893593. The reversal of 646783893504 is 405398387646.

646783893504 is a `hidden beast` number, since 6 + 4 + 6 + 7 + 8 + 38 + 93 + 504 = 666.

It is a super-2 number, since 2×646783893504² (a number of 24 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4653121467 + ... + 4653121605.

Almost surely, 2^646783893504 is an apocalyptic number.

646783893504 is a gapful number since it is divisible by the number (64) 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 646783893504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1145036256000).

646783893504 is an abundant number, since it is smaller than the sum of its proper divisors (1643288618496).

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

646783893504 is an equidigital number, since it uses as much as digits as its factorization.

646783893504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221 (or 174 counting only the distinct ones).

The product of its (nonzero) digits is 104509440, while the sum is 63.

The spelling of 646783893504 in words is "six hundred forty-six billion, seven hundred eighty-three million, eight hundred ninety-three thousand, five hundred four".