644215053 has 8 divisors (see below), whose sum is σ = 875160288. Its totient is φ = 421373264.

The previous prime is 644215049. The next prime is 644215057. The reversal of 644215053 is 350512446.

644215053 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (644215049) and next prime (644215057).

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 644215053 - 2² = 644215049 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 644215053.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644215057) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2025675 + ... + 2025992.

It is an arithmetic number, because the mean of its divisors is an integer number (109395036).

Almost surely, 2^644215053 is an apocalyptic number.

It is an amenable number.

644215053 is a deficient number, since it is larger than the sum of its proper divisors (230945235).

644215053 is a wasteful number, since it uses less digits than its factorization.

644215053 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4051723.

The product of its (nonzero) digits is 14400, while the sum is 30.

The square root of 644215053 is about 25381.3918649076. The cubic root of 644215053 is about 863.6616245589.

Adding to 644215053 its reverse (350512446), we get a palindrome (994727499).

The spelling of 644215053 in words is "six hundred forty-four million, two hundred fifteen thousand, fifty-three".