644464335 has 32 divisors (see below), whose sum is σ = 1069589952. Its totient is φ = 331084800.

The previous prime is 644464333. The next prime is 644464351. The reversal of 644464335 is 533464446.

It is not a de Polignac number, because 644464335 - 2¹ = 644464333 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 644464293 and 644464302.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644464333) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 50307 + ... + 61803.

It is an arithmetic number, because the mean of its divisors is an integer number (33424686).

Almost surely, 2^644464335 is an apocalyptic number.

644464335 is a deficient number, since it is larger than the sum of its proper divisors (425125617).

644464335 is a wasteful number, since it uses less digits than its factorization.

644464335 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11643.

The product of its digits is 414720, while the sum is 39.

The square root of 644464335 is about 25386.3021135415. The cubic root of 644464335 is about 863.7730094824.

The spelling of 644464335 in words is "six hundred forty-four million, four hundred sixty-four thousand, three hundred thirty-five".