647555 has 8 divisors (see below), whose sum is σ = 789072. Its totient is φ = 510048.

The previous prime is 647551. The next prime is 647557. The reversal of 647555 is 555746.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 647555 - 2² = 647551 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (647551) 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, 632 + ... + 1301.

It is an arithmetic number, because the mean of its divisors is an integer number (98634).

2⁶⁴⁷⁵⁵⁵ is an apocalyptic number.

647555 is a deficient number, since it is larger than the sum of its proper divisors (141517).

647555 is a wasteful number, since it uses less digits than its factorization.

647555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2005.

The product of its digits is 21000, while the sum is 32.

The square root of 647555 is about 804.7080215830. The cubic root of 647555 is about 86.5151610077.

Subtracting from 647555 its reverse (555746), we obtain a square (91809 = 303²).

The spelling of 647555 in words is "six hundred forty-seven thousand, five hundred fifty-five".