644104401 has 8 divisors (see below), whose sum is σ = 858931584. Its totient is φ = 429340080.

The previous prime is 644104361. The next prime is 644104411. The reversal of 644104401 is 104401446.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 644104401 - 2¹¹ = 644102353 is a prime.

It is not an unprimeable number, because it can be changed into a prime (644104411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19416 + ... + 40806.

It is an arithmetic number, because the mean of its divisors is an integer number (107366448).

Almost surely, 2^644104401 is an apocalyptic number.

It is an amenable number.

644104401 is a deficient number, since it is larger than the sum of its proper divisors (214827183).

644104401 is a wasteful number, since it uses less digits than its factorization.

644104401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31431.

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 644104401 is about 25379.2119854025. The cubic root of 644104401 is about 863.6121734955.

Adding to 644104401 its reverse (104401446), we get a palindrome (748505847).

The spelling of 644104401 in words is "six hundred forty-four million, one hundred four thousand, four hundred one".