644162401 has 8 divisors (see below), whose sum is σ = 658224000. Its totient is φ = 630115728.

The previous prime is 644162383. The next prime is 644162411. The reversal of 644162401 is 104261446.

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

It is a cyclic number.

It is not a de Polignac number, because 644162401 - 2⁵ = 644162369 is a prime.

It is a super-3 number, since 3×644162401³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 644162401.

It is not an unprimeable number, because it can be changed into a prime (644162411) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 162495 + ... + 166411.

It is an arithmetic number, because the mean of its divisors is an integer number (82278000).

Almost surely, 2^644162401 is an apocalyptic number.

It is an amenable number.

644162401 is a deficient number, since it is larger than the sum of its proper divisors (14061599).

644162401 is a wasteful number, since it uses less digits than its factorization.

644162401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7463.

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 644162401 is about 25380.3546271521. The cubic root of 644162401 is about 863.6380947606.

The spelling of 644162401 in words is "six hundred forty-four million, one hundred sixty-two thousand, four hundred one".