644254294448 has 20 divisors (see below), whose sum is σ = 1248861619080. Its totient is φ = 321967425024.

The previous prime is 644254294339. The next prime is 644254294477. The reversal of 644254294448 is 844492452446.

It is a happy number.

It is a hoax number, since the sum of its digits (56) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 644254294393 and 644254294402.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9949358 + ... + 10013901.

It is an arithmetic number, because the mean of its divisors is an integer number (62443080954).

Almost surely, 2^644254294448 is an apocalyptic number.

It is an amenable number.

644254294448 is a deficient number, since it is larger than the sum of its proper divisors (604607324632).

644254294448 is a wasteful number, since it uses less digits than its factorization.

644254294448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19965284 (or 19965278 counting only the distinct ones).

The product of its digits is 35389440, while the sum is 56.

The spelling of 644254294448 in words is "six hundred forty-four billion, two hundred fifty-four million, two hundred ninety-four thousand, four hundred forty-eight".