644530038 has 8 divisors (see below), whose sum is σ = 1289060088. Its totient is φ = 214843344.

The previous prime is 644530037. The next prime is 644530039. The reversal of 644530038 is 830035446.

It is an interprime number because it is at equal distance from previous prime (644530037) and next prime (644530039).

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

644530038 is an admirable number.

It is a super-3 number, since 3×644530038³ (a number of 27 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 644529990 and 644530008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644530037) 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 3 ways as a sum of consecutive naturals, for example, 53710831 + ... + 53710842.

It is an arithmetic number, because the mean of its divisors is an integer number (161132511).

Almost surely, 2^644530038 is an apocalyptic number.

644530038 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644530038 is a wasteful number, since it uses less digits than its factorization.

644530038 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107421678.

The product of its (nonzero) digits is 34560, while the sum is 33.

The square root of 644530038 is about 25387.5961445742. The cubic root of 644530038 is about 863.8023623089.

The spelling of 644530038 in words is "six hundred forty-four million, five hundred thirty thousand, thirty-eight".