644432504606366 has 16 divisors (see below), whose sum is σ = 1106127561250656. Its totient is φ = 275838827921376.

The previous prime is 644432504606347. The next prime is 644432504606483. The reversal of 644432504606366 is 663606405234446.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 28877588081 + ... + 28877610396.

It is an arithmetic number, because the mean of its divisors is an integer number (69132972578166).

Almost surely, 2^{644432504606366} is an apocalyptic number.

644432504606366 is a deficient number, since it is larger than the sum of its proper divisors (461695056644290).

644432504606366 is a wasteful number, since it uses less digits than its factorization.

644432504606366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57755199283.

The product of its (nonzero) digits is 179159040, while the sum is 59.

The spelling of 644432504606366 in words is "six hundred forty-four trillion, four hundred thirty-two billion, five hundred four million, six hundred six thousand, three hundred sixty-six".