646444202444645 has 32 divisors (see below), whose sum is σ = 847243321565184. Its totient is φ = 469591965460800.

The previous prime is 646444202444641. The next prime is 646444202444687. The reversal of 646444202444645 is 546444202444646.

It is not a de Polignac number, because 646444202444645 - 2² = 646444202444641 is a prime.

It is a Smith number, since the sum of its digits (59) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646444202444641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 230528630 + ... + 233315960.

It is an arithmetic number, because the mean of its divisors is an integer number (26476353798912).

Almost surely, 2^{646444202444645} is an apocalyptic number.

It is an amenable number.

646444202444645 is a deficient number, since it is larger than the sum of its proper divisors (200799119120539).

646444202444645 is a wasteful number, since it uses less digits than its factorization.

646444202444645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2792273.

The product of its (nonzero) digits is 283115520, while the sum is 59.

Subtracting from 646444202444645 its reverse (546444202444646), we obtain a palindrome (99999999999999).

The spelling of 646444202444645 in words is "six hundred forty-six trillion, four hundred forty-four billion, two hundred two million, four hundred forty-four thousand, six hundred forty-five".