644630294 has 16 divisors (see below), whose sum is σ = 1205542656. Its totient is φ = 251154600.

The previous prime is 644630279. The next prime is 644630297. The reversal of 644630294 is 492036446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644630297) 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, 2092802 + ... + 2093109.

It is an arithmetic number, because the mean of its divisors is an integer number (75346416).

Almost surely, 2^644630294 is an apocalyptic number.

644630294 is a deficient number, since it is larger than the sum of its proper divisors (560912362).

644630294 is a wasteful number, since it uses less digits than its factorization.

644630294 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4185931.

The product of its (nonzero) digits is 124416, while the sum is 38.

The square root of 644630294 is about 25389.5705753366. The cubic root of 644630294 is about 863.8471478502.

The spelling of 644630294 in words is "six hundred forty-four million, six hundred thirty thousand, two hundred ninety-four".