644633334 has 24 divisors (see below), whose sum is σ = 1397206200. Its totient is φ = 214800768.

The previous prime is 644633333. The next prime is 644633347. The reversal of 644633334 is 433336446.

644633334 is a `hidden beast` number, since 644 + 6 + 3 + 3 + 3 + 3 + 4 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644633333) 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, 69414 + ... + 78150.

It is an arithmetic number, because the mean of its divisors is an integer number (58216925).

Almost surely, 2^644633334 is an apocalyptic number.

644633334 is an abundant number, since it is smaller than the sum of its proper divisors (752572866).

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

644633334 is a wasteful number, since it uses less digits than its factorization.

644633334 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12844 (or 12841 counting only the distinct ones).

The product of its digits is 186624, while the sum is 36.

The square root of 644633334 is about 25389.6304423676. The cubic root of 644633334 is about 863.8485057816.

The spelling of 644633334 in words is "six hundred forty-four million, six hundred thirty-three thousand, three hundred thirty-four".