644500486 has 16 divisors (see below), whose sum is σ = 1118845440. Its totient is φ = 272717640.

The previous prime is 644500453. The next prime is 644500487. The reversal of 644500486 is 684005446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644500487) 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, 290260 + ... + 292471.

It is an arithmetic number, because the mean of its divisors is an integer number (69927840).

Almost surely, 2^644500486 is an apocalyptic number.

644500486 is a deficient number, since it is larger than the sum of its proper divisors (474344954).

644500486 is a wasteful number, since it uses less digits than its factorization.

644500486 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 582819.

The product of its (nonzero) digits is 92160, while the sum is 37.

The square root of 644500486 is about 25387.0141213968. The cubic root of 644500486 is about 863.7891601947.

The spelling of 644500486 in words is "six hundred forty-four million, five hundred thousand, four hundred eighty-six".