646867768646 has 32 divisors (see below), whose sum is σ = 1114493022720. Its totient is φ = 278487741600.

The previous prime is 646867768577. The next prime is 646867768663.

646867768646 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×646867768646² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1551491 + ... + 1923761.

It is an arithmetic number, because the mean of its divisors is an integer number (34827906960).

Almost surely, 2^646867768646 is an apocalyptic number.

646867768646 is a deficient number, since it is larger than the sum of its proper divisors (467625254074).

646867768646 is a wasteful number, since it uses less digits than its factorization.

646867768646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376460.

The product of its digits is 2341011456, while the sum is 74.

The spelling of 646867768646 in words is "six hundred forty-six billion, eight hundred sixty-seven million, seven hundred sixty-eight thousand, six hundred forty-six".