644025229 has 12 divisors (see below), whose sum is σ = 685135584. Its totient is φ = 605257664.

The previous prime is 644025227. The next prime is 644025241. The reversal of 644025229 is 922520446.

It is not a de Polignac number, because 644025229 - 2¹ = 644025227 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 644025194 and 644025203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644025227) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 282954 + ... + 285220.

It is an arithmetic number, because the mean of its divisors is an integer number (57094632).

Almost surely, 2^644025229 is an apocalyptic number.

It is an amenable number.

644025229 is a deficient number, since it is larger than the sum of its proper divisors (41110355).

644025229 is a wasteful number, since it uses less digits than its factorization.

644025229 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3284 (or 3267 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 34.

The square root of 644025229 is about 25377.6521569668. The cubic root of 644025229 is about 863.5767875630.

It can be divided in two parts, 644025 and 229, that multiplied together give a triangular number (147481725 = T₁₇₁₇₄).

The spelling of 644025229 in words is "six hundred forty-four million, twenty-five thousand, two hundred twenty-nine".