644004446402 has 16 divisors (see below), whose sum is σ = 989596518624. Its totient is φ = 314139396000.

The previous prime is 644004446369. The next prime is 644004446467. The reversal of 644004446402 is 204644400446.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3378377 + ... + 3563907.

It is an arithmetic number, because the mean of its divisors is an integer number (61849782414).

Almost surely, 2^644004446402 is an apocalyptic number.

644004446402 is a deficient number, since it is larger than the sum of its proper divisors (345592072222).

644004446402 is a wasteful number, since it uses less digits than its factorization.

644004446402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227905.

The product of its (nonzero) digits is 294912, while the sum is 38.

Adding to 644004446402 its reverse (204644400446), we get a palindrome (848648846848).

The spelling of 644004446402 in words is "six hundred forty-four billion, four million, four hundred forty-six thousand, four hundred two".