644543604342146 has 16 divisors (see below), whose sum is σ = 968526185356800. Its totient is φ = 321701556160608.

The previous prime is 644543604342133. The next prime is 644543604342181. The reversal of 644543604342146 is 641243406345446.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 644543604342091 and 644543604342100.

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 7 ways as a sum of consecutive naturals, for example, 92596451 + ... + 99313593.

It is an arithmetic number, because the mean of its divisors is an integer number (60532886584800).

Almost surely, 2^{644543604342146} is an apocalyptic number.

644543604342146 is a deficient number, since it is larger than the sum of its proper divisors (323982581014654).

644543604342146 is a wasteful number, since it uses less digits than its factorization.

644543604342146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6802033.

The product of its (nonzero) digits is 79626240, while the sum is 56.

The spelling of 644543604342146 in words is "six hundred forty-four trillion, five hundred forty-three billion, six hundred four million, three hundred forty-two thousand, one hundred forty-six".