644727216590 has 8 divisors (see below), whose sum is σ = 1160508989880. Its totient is φ = 257890886632.

The previous prime is 644727216589. The next prime is 644727216677. The reversal of 644727216590 is 95612727446.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32236360820 + ... + 32236360839.

It is an arithmetic number, because the mean of its divisors is an integer number (145063623735).

Almost surely, 2^644727216590 is an apocalyptic number.

644727216590 is a deficient number, since it is larger than the sum of its proper divisors (515781773290).

644727216590 is a wasteful number, since it uses less digits than its factorization.

644727216590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64472721666.

The product of its (nonzero) digits is 5080320, while the sum is 53.

The spelling of 644727216590 in words is "six hundred forty-four billion, seven hundred twenty-seven million, two hundred sixteen thousand, five hundred ninety".